Frey's syndrome after elective thyroidectomy: a case report.

This case report documents the case of a 41-year-old Caucasian woman who developed a Frey's syndrome after elective thyroidectomy. This patient developed a sudden redness on one side of the face in the recovery room after a total thyroidectomy under general anaesthesia. All other vital signs of the patient remained normal. There were no signs of infection. After a few hours the symptoms disappeared without any treatment. Frey's syndrome is a disorder characterised by unilateral flushing or sweating of the facial skin. This syndrome can occur after parotidectomy or after trauma, injury or inflammation of the parotid, the submandibular glands, or of cervical and thoracic parts of the sympathetic trunk. Frey's syndrome normally results from aberrant regeneration of auriculotemporal nerve fibers to sweat glands in the skin. This case describes a self-limiting Frey' s syndrome after irritation of the cervical portion of the truncus sympathicus following total thyroidectomy.

Beta-adrenergic blocking drugs in the perioperative period.

During the last years increasing evidence has indicated that patients at risk for coronary artery disease may benefit from beta-adrenergic blocking therapy in the perioperative setting. It has been demonstrated that even a relatively brief treatment with beta-adrenergic blocking drugs decreases the incidence of perioperative myocardial ischemia. Even more important is the observation that this reduction in perioperative ischemic events ultimately results in a decrease in long term cardiac morbidity and mortality. Despite overwhelming evidence on the beneficial effects of beta-adrenergic blocking in patients with coronary artery disease, many clinicians still feel some reluctance to use this type of drugs in the perioperative period. We organized a meeting to search for the major objectives that keep anesthetists from implementing prophylactic beta blocking therapy in their daily clinical practice. In this brief review we summarize the results of this meeting and discuss the current knowledge on this subject.

Comparison between the cuffed oropharyngeal airway and the laryngeal mask with respect to breathing pattern and capnography.

This study evaluates spontaneous breathing and CO2-monitoring under sevoflurane anesthesia with a cuffed oropharyngeal (COPA) or laryngeal mask (LMA) as airway. Forty patients (ASA I-II) scheduled for varicose vein surgery were given 2 mg.kg-1 propofol for insertion of a COPA or a LMA. Anesthesia was maintained with sevoflurane at 2.5 vol% in 40/60% O2/N2O, while the patients breathed spontaneously. Arterial and end-tidal CO2 partial pressures (PaCO2, PE'CO2), respiratory rate (RR), tidal volume (VT) and expired minute volume (EMV) were recorded at different times before and during the procedure. The dead space (VD) was calculated from the modified Bohr equation. The PaCO2 and the PE'CO2 were generally lower in the LMA group as compared to the COPA group during most of the procedure. EMV was also higher in the LMA group as compared to the COPA group. This difference becomes statistically significant 5 min. before the end of surgery (6.22 +/- 0.34 vs. 5.23 +/- 0.39 L.min-1). RR was consistently higher in the LMA group, while VT and VD were similar. Correlation of PE'CO2 and PaCO2 was 0.87 when measured in the COPA group and 0.88 in the LMA group. The prediction of PaCO2 by PE'CO2 was more sensitive in the LMA group as compared to the COPA group. We conclude that spontaneous breathing is better with the LMA.

Isoflurane, desflurane and sevoflurane for carotid endarterectomy.

After carotid endarterectomy under general anaesthesia, the rapid elimination of desflurane and sevoflurane may allow earlier postoperative neurological assessment than after the use of isoflurane. However, desflurane may be associated with tachycardia and hypertension and may therefore increase cardiovascular risk. We investigated haemodynamic and recovery characteristics in patients scheduled for carotid endarterectomy who were anaesthetised with isoflurane, sevoflurane or desflurane. No significant peri-operative differences were noted in cardiac index or ST segment analysis. The times to extubation, movement on command and consciousness were shorter after desflurane and sevoflurane than after isoflurane anaesthesia. Postoperative pain, nausea, vomiting and shivering were similar in the three study groups.

Successful prolonged cardiopulmonary resuscitation after a combined intoxication with a tricyclic antidepressant, a benzodiazepine and a neuroleptic.

We report the case of a patient who co-ingested a tricyclic antidepressant (amitriptyline), benzodiazepines (alprazolam and lormetazepam) and a neuroleptic drug (prothipendyl). Major neurologic and cardiac symptoms occurred including a prolonged cardiac arrest. The cardiopulmonary resuscitation phase was complicated by a haematoma of the liver treated by a left hepatectomy. The clinical features and management of this combined intoxication are discussed.

Antagonistic effects of naloxone and naloxonazine on sufentanil-induced antinociception and respiratory depression in rats.

Several binding studies in rodent brain homogenates have revealed two distinct micro-opiate binding sites based on differences in binding affinity of several opiate peptides and opiate alkaloids. Naloxonazine (NLZ), which preferentially binds to the high affinity micro(1) sites, is often used to discriminate between pharmacological effects mediated by micro(1) and micro(2) binding sites. The present series of experiments were undertaken to compare the opioid antagonistic properties of naloxonazine and naloxone (NLX) (a non-selective micro(1)-antagonist) on intravenous (i.v.) and intrathecal (i.t.) sufentanil (SUF)-induced antinociception and respiratory depression. The opioid antagonists were given either intravenously at 5 min after SUF, or subcutaneously (s.c.) 24 h prior to the opioid. Intravenous NLX and NLZ reduced the i.v. and i. t. SUF-induced antinociception, hypercapnia and hypoxia when given directly after the opioid. There were no major differences in activity between both antagonists. Pretreatment with 30 mg/kg NLX did not reverse the i.v. or i.t. SUF-induced antinociception and respiratory depression. Subcutaneous pretreatment with doses up to 30 mg/kg NLX only partially antagonized the i.v. SUF-induced antinociception, while a complete reversal was present of the opioid-induced hypercapnia and hypoxia. With regard to i.t. SUF, doses up to 30 mg/kg NLZ were unable to reduce the antinociception. The respiratory depression was partially affected; with 30 mg/kg NLZ, the i.t. SUF-induced hypercapnia returned to baseline levels, whereas the SUF-induced hypoxia was only minimally affected. These results challenge the classical view of the selectivity of NLZ for the high affinity micro(1) binding sites. They further fail to conform an exclusive role for micro(2) receptor sites in the respiratory depression and spinal analgesia induced by a strong lipophilic opioid such as SUF in rats.

The effects of intravenous naltrindole and naltrindole 5'-isothiocyanate on sufentanil-induced respiratory depression and antinociception in rats.

Although the interactions between the mu- and the delta-opiate receptor subtypes are well documented with regard to supraspinal analgesia, less is known about the mutual interactions on respiratory depression. To clarify the functional interactions between both opiate receptor subtypes with regard to antinociception and respiratory depression, male Wistar rats were intravenously injected with 2.5 microg/kg of the mu-opiate agonist sufentanil and subsequently intravenously challenged with the delta antagonist naltrindole (NTI) or naltrindole 5'-isothiocyanate (5'-NTII), a delta-2 antagonist. Antinociception was measured by means of the tail-flick latency, and respiratory depression was evaluated by means of analysis of PaCO2, PaO2, and oxygen saturation. To quantify the antagonistic properties of NTI and 5'-NTII, mean areas under the curve were calculated for groups treated with sufentanil, control vehicle, and sufentanil plus a dose of the antagonists. NTI, but not 5'-NTII, antagonized the sufentanil-induced antinociception at 10 mg/kg NTI. Below this dose the effects were inconsistent. The sufentanil-induced hypercapnia and hypoxia were diminished with 10 mg/kg NTI or 5'-NTII. These data indicate that NTI antagonizes the sufentanil-induced antinociception and respiratory depression in rats. A dissociation between the antinociception and respiratory depression following intravenous sufentanil could be obtained with 10 mg/kg 5'-NTII pointing to different regulatory effects of opiate delta receptor subtypes on mu-opiate agonist-induced behavioral effects.

Propofol concentrations in follicular fluid during general anaesthesia for transvaginal oocyte retrieval.

Propofol (Diprivan) is an i.v. anaesthetic used for general anaesthesia. The purpose of this study was to measure the propofol concentration in arterial blood and follicular fluid in patients during transvaginal oocyte retrieval. After approval by the University Ethics Committee, 30 women participated in this prospective study. Following induction of anaesthesia with 0.5 mg alfentanil and 2 mg.kg-1 propofol i.v., a continuous infusion of propofol at 10 mg.kg-1.h-1 was used for maintenance of anaesthesia. Follicular fluid and arterial blood samples were aspirated simultaneously at fixed intervals during the surgical procedure and propofol assayed by high pressure liquid chromatography (HPLC). The mean follicular fluid concentration of propofol increased linearly with time from 0.10 +/- 0.02 microgram.ml-1 to 0.57 +/- 0.06 microgram.ml-1 and was strongly related to the cumulative dose of propofol administered. The absorption of propofol was time-dependent. There was no correlation between the concentration of propofol in the follicular fluid and the arterial blood concentration of the drug. In conclusion, a propofol-based anaesthetic technique resulted in significant concentrations of this agent in follicular fluid, related to the dose administered and to the duration of propofol administration.

Comparison of assisted reproductive technology performance after oocyte retrieval under general anaesthesia (propofol) versus paracervical local anaesthetic block: a case-controlled study.

Propofol (Dipirivan) is an intravenous anaesthetic drug used for general anaesthesia. Although frequently used as a general anaesthetic for ultrasound procedures, its use during transvaginal oocyte retrieval is currently being debated. A total of 202 patients undergoing fertility treatment was included in a prospective, matched, controlled study, in which we compared fertilization rates and embryo development in terms of morphological quality and speed of development and the implications for reproductive outcome and pregnancy following general anaesthesia using either propofol or a paracervical local anaesthetic block during oocyte collection. There were no differences between the fertilization rates and the embryo cleavage characteristics for the two groups. The initial implantation rate per transferred embryo after general anaesthesia was similar to that after paracervical local anaesthetic block (13.4 versus 18.6%; P = 0.10). The ongoing clinical implantation rates per embryo transferred were also similar in the two groups.

Effects of diluent volume of a single dose of epidural bupivacaine in parturients during the first stage of labor.

BACKGROUND AND OBJECTIVES: 0.1% bupivacaine for obstetric epidural analgesia is given by infusion, using a loading dose of a higher concentration alone or in combination with opioid analgesics. A single dose of 0.1% without any additive for relief of first-stage labor pain has not yet been documented. METHODS: Fifty-eight primiparae in active labor and with less than 5 cm cervical dilatation received 20 mg epidural bupivacaine diluted in 4 mL [group 1: 0.5% (I)], 10 mL [group 2: 0.2% (II)], or 20 mL [group 3: 0.1% (III)]. Pain relief, dermatomal spread, and motor block were assessed. RESULTS: Visual analog pain scale (VAS) was significantly lower in group 2 (0.88 +/- 1.34) and group 3 (0.25 +/- 0.61) than in group 1 (4.37 +/- 2.57). Onset and time to maximum analgesia was significantly shorter in group 2 than in group 3. Mean duration of analgesia was 120 +/- 21 minutes in group 3, 100 +/- 26 in group 2, and 43 +/- 21 in group 1. The mean numbers and upper limits of dermatomes blocked did not differ between groups 2 and 3, but were higher than in group 1. Motor blocks in groups 2 and 3 were more extensive than in group 1 with no difference between groups 2 and 3. Ten mL 0.2% or 20 mL 0.1% epidural bupivacaine results in a similar degree of pain relief, superior to that following 4 mL 0.5%, while duration was longest after 20 mL 0.1%. CONCLUSIONS: Analgesia lasts significantly longer following 20 mL 0.1% bupivacaine than following 10 mL 0.2% bupivacaine when given for first-stage labor pain. Four milliliters 0.5% bupivacaine results in inadequate pain relief.

Effects of chlordiazepoxide on opioid-induced antinociception and respiratory depression in restrained rats.

This study investigates the influence of possible stress due to housing in Bolman cages on antinociception and on respiratory depression following opioid administration. To evaluate the functional role of this stressor and to modulate it, rats were subcutaneously pretreated with the anxiolytic chlordiazepoxide (CDP; 10 mg/kg) or saline (SAL) before the immobilization in the Bolman cages and before the intravenous administration of small doses of morphine (MOR), sufentanil (SUF), or vehicle (VEH). Antinociception, respiratory impairment and stress were evaluated by means of the tail-flick latency, blood gas analysis, and serum corticosterone (CS), adrenocorticotropic hormone (ACTH), and prolactin (PRL) determinations. The results demonstrated that 10 mg/kg CDP did not alter the antinociceptive effects of low doses of morphine and sufentanil. CDP pretreatment differentially affected the various blood gas parameters. Compared to vehicle pretreatment, there was a larger decrease in PaO2 following MOR and SUF in the CDP-pretreated rats. The effects were most pronounced at the lowest doses of both opioids. A CDP potentiation was also observed for the short-lasting raises in PaCO2 with the lowest concentrations of the opioids. At higher concentrations of the opioids, CDP was without any effect. With regard to the stress hormones, immobilization and an intravenous injection resulted in increases in CS and PRL in both CDP- and VEH-pretreated rats. ACTH did not change in these controls. SUF prevented the CS raises independent of a CDP pretreatment, while ACTH only increased in the SUF plus CDP groups, pointing to a stress-reducing effect of SUF. Also, MOR without CDP prevented the increases in CS, but the opioid intrinsically increased ACTH. These results indicate that restraint in Bolman cages in the present setup, with animals recovering for several hours in these cages after being equipped with an arterial catheter, is stressful but without any significant effect on the opioid-induced antinociception. Pretreatment with an anxiolytic benzodiazepine only minimally affected the outcome of the opioids on respiratory depression and pointed to a stress-reducing effect of low doses of the opioids, especially sufentanil.

Interaction between sufentanil and U-50488H with respect to antinociception and respiratory depression in rats.

BACKGROUND: Opiate receptors have been argued to differentially regulate analgesia and respiratory depression. In order to validate possible interactions between the opiate mu- and kappa-receptors, interactions between sufentanil and U-50488H were studied in rats. METHODS: Rats equipped with an arterial catheter were tested in the tail flick latency (TFL) test after intravenous treatment with sulentanil (a mu-agonist), U-50488H (a kappa-agonist) or fixed ratio combinations of both drugs. Simultaneously, respiratory changes were monitored by blood gas analysis. RESULTS: The ED50s of sufentanil for a TFL > 6.0 and > or = 10.0 s were 0.0002 and 0.00059 mg/kg. For U-50488H the corresponding values were 1.53 and 8.11 mg/kg. Using a fixed dose ratio of 1/10,000, an additivity was demonstrated between sufentanil and U-50488H in terms of antinociception. With regard to respiratory parameters, PaCO2 significantly increased after all doses of sufentanil early after treatment. At the higher doses tested, there was also a decrease in PaO2 and O2 saturation. For U-50488H only the highest doses resulted in an early and small shift in PaCO2. The combination of sufentanil/U-50488H resulted in only a small increase in PaCO2 at the highest dose regimen tested. CONCLUSION: The results presented here demonstrate that drug mixtures of sufentanil and U-50488H can be additive with respect to antinociception with additionally less risk for respiratory side-effects, as compared with sufentanil alone. Therefore, a combination of mu- and kappa-opiate-receptor agonists might be more beneficial than each agent alone.

Anaesthetic management of caesarean section in a parturient with acute myelodysplastic syndrome.

A 34-year-old pregnant woman developed a myelodysplastic syndrome during pregnancy which resulted in a refractory anaemia and an extreme thrombocytopenia. The report describes the anaesthetic management of elective caesarean section and successful childbirth in this patient. Following replacement therapy with packed red cells and platelets, general anaesthesia was used for the procedure.

The quality of breathing and capnography during laryngeal mask and facemask ventilation.

Clinical measures of ventilation and the relationship between arterial and end-tidal carbon dioxide tensions were studied during inhalational anaesthesia in 18 patients using a laryngeal mask airway or a facemask. Tidal volumes were similar in both groups but expired minute volume, respiratory rate and physiological deadspace ventilation were significantly increased in the facemask group. Both end-tidal and arterial carbon dioxide tensions were higher in the laryngeal mask group. Mean arterial to end-tidal carbon dioxide tension differences ranged from 0.13 to 4.13 kPa in the facemask group and from 0-1.73 kPa with the laryngeal mask airway. Pooled data analysis revealed a better correlation between arterial and end-tidal carbon dioxide tensions during laryngeal mask ventilation as compared to facemask breathing. With both techniques the arterial to end-tidal carbon dioxide tension difference was related to respiratory rate and physiological deadspace ventilation. Estimation of arterial carbon dioxide partial pressure by monitoring end-tidal carbon dioxide tension is more reliable with the laryngeal mask airway than during facemask breathing, in particular at small tidal volumes.

Efficacy and safety of oral tramadol and pentazocine for postoperative pain following prolapsed intervertebral disc repair.

In this multicenter double-blind randomized study the analgesic efficacy and safety of 50 mg tramadol was compared against 50 mg pentazocine by mouth in the treatment of 160 patients with acute pain following prolapsed intervertebral disc repair. The day of surgery patients were treated with parenteral opioids. The study started the morning after surgery. A wash out period of four hours was allowed after parenteral analgesics. Pain assessment was made using a visual analogue scale (VAS) and a verbal rating scale (VRS) during a six hours observation period. Remedication with the same drug at the same dosage was allowed if pain relief was unsatisfactory. Overall analgesic activity and spontaneously reported side effects were also registered. Results showed both treatments provided equivalent effective analgesia for the six hours observation period. The global assessment of analgesia by patient and observer was not significantly different for both treatments, although less additional medication was required in the pentazocine group. Side effects were quite common in both groups, and occurred more frequently in the pentazocine group.

Postoperative pain treatment after cholecystectomy with epidural sufentanil at lumbar or thoracic level.

The difference in analgesic activity following lumbar (group I) or thoracic (group II) epidural administration of 50 micrograms sufentanil was studied after cholecystectomy. Fifteen patients in each group were evaluated for pain relief using a linear analog scale (LAS), heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peak expiratory flow (PEF), forced vital capacity (FVC), forced expiratory volume (FEV1) and arterial CO2 tension (PaCO2). In five additional patients in each group 75 micrograms sufentanil was injected for determination of serum levels. Pain scores were lower than three in both groups after 10 min, while mean pain scores remained below one from 20 min until 2 h following injection in both groups. Satisfactory pain relief lasted for 4 h. RR was significantly decreased from two until 360 min. in the lumbar group and from five until 120 min in the thoracic group. PaCO2 was raised in both groups only during the first hour. PEF and FVC were significantly improved compared to control 1, 2 and 4 h following injection. Serum sufentanil levels reached a maximum of 0.299 +/- 0.052 ng.ml-1 in the lumbar group and 0.377 +/- 0.076 ng.ml-1 in the thoracic group after 5 min. There were no significant differences between the two groups in the variables studied.

Haemodynamic effects of isoflurane during propofol anaesthesia.

We have studied haemodynamic responses to 0, 0.25, 0.5, 0.75 and 1 MAC isoflurane administration in 10 patients during a zero-order propofol infusion and normocapnia. Isoflurane reduced mean arterial pressure (MAP), systemic vascular resistance and left ventricular stroke work in a dose-dependent manner (29%, 38% and 33%, respectively, at 1 MAC), while cardiac output (CO), stroke volume (SV) and heart rate were not affected significantly. Mean pulmonary artery pressure, pulmonary vascular resistance and right ventricular stroke work decreased by 13%, 10% and 17%, respectively (not significant). Pulmonary capillary wedge pressure and central venous pressure were affected minimally, while intrapulmonary shunting and PaO2 remained constant. It is concluded that administration of isoflurane during infusion of propofol caused a dose-dependent decrease in MAP as a result of afterload reduction without modification in CO or SV.

Thoracic epidural bupivacaine-fentanyl anesthesia for percutaneous cholecystolithotomy in high-risk patients.

BACKGROUND AND OBJECTIVES: The efficacy of a thoracic epidural block was assessed in 12 high-risk patients scheduled for elective percutaneous cholecystolithotomy. METHODS: A thoracic epidural catheter was inserted at level T8-9. The amount of 0.5% bupivacaine to block two thoracic epidural segments was calculated, adapted to age, height, and epidural level, and administered with 50 micrograms fentanyl. Hemodynamic and respiratory variables and patients' pain and movement were assessed throughout the procedure. RESULTS: Anesthesia was obtained with a minimal dose of local anesthetic. All patients were satisfied with this method. Neither hemodynamic nor respiratory impairment were observed after epidural injection. However, vagal reactions reported in other studies occurred in two patients upon puncture of the gallbladder. CONCLUSIONS: This minimally invasive anesthetic technique seems to be a good alternative for high-risk patients. However, careful monitoring of heart rate and blood pressure remains mandatory throughout the procedure.

Onset of epidural blockade after plain or alkalinized 0.5% bupivacaine.

This double-blind study investigated the effect of adding 1.4% bicarbonate to 0.5% bupivacaine on onset time of sensory and motor blockade after epidural administration. Forty patients were randomly divided into one of two groups. Group 1 received 20 mL of 0.5% bupivacaine (pH, 5.58 +/- 0.12) and group 2 received 20 mL of 0.5% bupivacaine + 0.6 mL of 1.4% bicarbonate (pH, 6.53 +/- 0.06). Onset of temperature sensation loss occurred at L-1 after 5 min in both groups. The first signs of motor impairment were seen after 4 min in three patients in group 1 and two patients in group 2. Maximum motor blockade was reached after 30 min in group 1 and after 36 min in group 2. No difference in motor blockade or upward spread of anesthesia was noted between the two groups. The authors conclude that alkalinization of 0.5% bupivacaine offers no improvement in the onset of epidural blockade.