SAMBA Talks eNewsletter - September, 2003

FROM THE LITERATURE: - TOP

CANADIAN JOURNAL OF ANESTHESIA - TOP

The gum elastic bougie eases tracheal intubation while applying cricoid pressure compared to a stylet
Takashi Noguchi, MD, Kazunori Koga, MD, Yousuke Shiga, MD and Akio Shigematsu, MD
Canadian Journal of Anesthesia 50:712-717 (2003)

Purpose: To compare the ease of tracheal intubation facilitated by the gum elastic bougie or the malleable stylet while applying cricoid pressure.
Methods: Sixty American Society of Anesthesiologists I–III adult patients undergoing elective surgeries participated in this study. After induction of anesthesia with 2.5 mg•kg ^-1 propofol and vecuronium 0.1 mg•kg^-1, the laryngeal view was assessed without and with cricoid pressure. Patients were allocated randomly into two groups: a gum elastic bougie or stylet group. One of the two devices was used for tracheal intubation while applying cricoid pressure. The duration and ease of tracheal intubation was recorded.
Main results: In 58 patients, the trachea was intubated at the first attempt. In the stylet group, tracheal intubation was difficult and needed more time, especially when the glottic opening was not visible. In the bougie group, the duration and ease of intubation was not influenced by laryngeal view. In the remaining two patients with Cook’s modified 3b laryngeal view, it was impossible to intubate the trachea with these devices.
Conclusions: Applying cricoid pressure worsened laryngeal view. The use of a gum elastic bougie was more effective than the use of a stylet to facilitate intubation.

BRITISH JOURNAL OF ANAESTHESIA - TOP

Supplemental oxygen for prevention of nausea and vomiting after breast surgery
S. Purhonen, M. Niskanen, M. Wüstefeld, P. Mustonen and M. Hynynen
Br J Anaesth 2003; 91: 284–7

Background: Administration of supplemental oxygen 80% has been shown to halve the incidence of postoperative nausea and vomiting (PONV). We tested the efficacy of supplemental oxygen 50% in decreasing the incidence of PONV after breast surgery.
Methods: One hundred patients receiving standardized sevoflurane anaesthesia were randomly assigned to two groups: oxygen 30% administration (Group 30); and oxygen 50% administration (Group 50). Oxygen was administered during surgery and for 2 h from the end of surgery.
Results: The incidence of PONV over 24 h after surgery showed no difference between the groups: 82% in Group 30 and 89% in Group 50. However, during the postoperative oxygen administration, eight patients vomited in Group 30, compared with none in Group 50 (P<0.05). After oxygen therapy ceased, there was no difference in the incidence of vomiting between the groups. Nausea and need for rescue antiemetics did not differ between the groups.
Conclusion: The incidence of vomiting decreased during the short postoperative administration of supplemental oxygen 50%. However, perioperative oxygen 50% administration did not prevent PONV over the 24-h follow-up period in patients undergoing breast surgery performed under general anaesthesia.

Repeated inadvertent endobronchial intubation during laparoscopy (Case Report)
M. Mackenzie and K. MacLeod
Br J Anaesth 2003; 91: 297–8

Inadvertent endobronchial intubation occurred twice during laparoscopic surgery, with two different causes. Radiography was the only means of definitive diagnosis.

ANESTHESIA AND ANALGESIA - TOP

A Comparison of Two Regional Anesthetic Techniques for Outpatient Knee Arthroscopy
Julia E. Pollock, MD, Michael F. Mulroy, MD, Elyssa Bent, MD, and Nayak L. Polissar, PhD
Anesth Analg 2003;97:397-401

IMPLICATIONS: Small dose lidocaine spinal anesthesia and 3% 2-chloroprocaine epidural anesthesia provided comparable discharge times for outpatient knee arthroscopy. The incidence of transient neurologic symptoms with small-dose lidocaine spinal anesthesia was 12%.

A Comparison of the Costs and Efficacy of Ondansetron and Dolasetron in the Prophylaxis of Postoperative Vomiting in Pediatric Patients Undergoing Ambulatory Surgery
Olutoyin Olutoye, MD, Ellen C. Jantzen, MD, Rhonda Alexis, MD, Donna Rajchert, MD, Mark S. Schreiner, MD, and Mehernoor F. Watcha, MD
Anesth Analg 2003;97:390-396

Postoperative vomiting (POV) after ambulatory surgery remains a major problem. We designed this study to determine the smallest dose of dolasetron equivalent to the Food and Drug Administration approved dose of ondansetron 100 mcg/kg IV, for the prophylaxis of POV in children undergoing surgery. In this double-blinded controlled study, 204 healthy ASA I–II children aged 2–12 yr, undergoing superficial ambulatory (day-case) surgery, were randomized to receive either ondansetron 100 mcg/kg IV, or dolasetron 45, 175, 350, or 700 mcg/kg IV during a standardized perioperative regimen. The primary end-point was the incidence of complete response, defined as the absence of POV symptoms. Costs were calculated from the perspective of the hospital using a previously described model. The incidence of early (0–6 h) and 24-h emesis was more frequent in the dolasetron 45 mcg/kg group compared with the dolasetron 350 and 700 mcg/kg groups and with the ondansetron group. Repeated POV occurred more often when dolasetron was used in a dose <350 mcg/kg. There were no significant differences in emesis rates between the dolasetron 175, 350, and 700 mcg/kg groups or between these groups and the ondansetron 100 mcg/kg group. The smallest dose of dolasetron with acceptable equivalent efficacy and patient satisfaction scores to ondansetron 100 mcg/kg was 350 mcg/kg. Institutional costs for managing POV were less with dolasetron 350 mcg/kg than with ondansetron.
IMPLICATIONS: This randomized double-blinded dose-ranging study concluded that dolasetron, 350 mcg/kg IV, was the smallest dose that provided acceptable equivalent efficacy and patient satisfaction scores to ondansetron, 100 mcg/kg IV, for the prophylaxis of postoperative vomiting in children undergoing outpatient surgery. However, with this dose, the costs to the institution for managing postoperative vomiting were less.

A Comparison of Three Different Concentrations of Levobupivacaine for Caudal Block in Children
Giorgio Ivani, MD, Pasquale De Negri, MD, Per-Arne Lonnqvist, PhD, Staffan Eksborg, PhD, Valeria Mossetti, MD, Roberto Grossetti, MD, Simona Italiano, MD, Franca Rosso, MD, Federica Tonetti, MD, and Luigi Codipietro, MD
Anesth Analg 2003;97:368-371

We investigated three different concentrations of levobupivacaine (0.125%, 0.20%, and 0.25%; n = 20 in each group) for caudal blockade in a prospective, randomized, observer-blinded fashion in children (1–7 yr) undergoing subumbilical surgery. The duration of postoperative analgesia was assessed as the time to first administration of supplemental analgesia (based on a Childrens and Infants Postoperative Pain Scale score of 4), and the degree of immediate postoperative motor blockade was determined by use of a 3-point scale. A dose-response relationship was observed both with regard to median duration of postoperative analgesia (0.125%, 60 min; 0.20%, 118 min; 0.25%, 158 min) and the number of patients with evidence of early postoperative motor blockade (0.125%, 0; 0.20%, 4; 0.25%, 8). The 0.125% concentration was associated with significantly less early motor blockade (P = 0.003) but was found to result in a significantly shorter duration of postoperative analgesia (P < 0.05). Based on these results, the use of 0.20% levobupivacaine might represent the best clinical option if a plain levobupivacaine solution is to be used for caudal blockade in children.
IMPLICATIONS: The use of 0.125% levobupivacaine for caudal blockade (1 mL/kg) in children (1–7 yr) was associated with less early postoperative motor blockade but a shorter duration of postoperative analgesia compared with 0.20% and 0.25% solutions.

The Relationship Between Expired Concentration of Sevoflurane and Sympathovagal Tone in Children
Eric Wodey, MD PhD, Lotfi Senhadji, PhD, Patrick Pladys, MD PhD, François Carre, MD PhD, and Claude Ecoffey, MD
Anesth Analg 2003;97:377-382

In children, sevoflurane depresses parasympathetic tone during induction more than halothane. The effects of sevoflurane on parasympathetic activity could explain the difference in heart rate (HR) changes described between infants and children. In this study, we sought to determine the relationship between the end-tidal concentration of sevoflurane and sympathetic and parasympathetic tone in children by spectral analysis of RR intervals. Thirty-three children, ASA physical status I, who required elective surgery were studied. In 10 children (Group A), recordings were performed while gradually decreasing the inspired sevoflurane concentration from 8% to the beginning of clinical awakening. In 23 other children (Group B), recordings were performed while children were awake and at a steady-state of 1 and 2 minimum alveolar anesthetic concentration of sevoflurane. A time-varying autoregressive modeling of the interpolated RR sequences was performed, and spectral density in low-frequency (LF; 0.04–0.15 Hz) and high-frequency (HF; 0.15–0.55 Hz) bands was calculated. In Group A, HR slowing paralleled the decrease in expired sevoflurane concentration. Conversely, the decrease in expired concentration of sevoflurane led to an increase in systolic blood pressure (SBP), HF, LF, and LF/HF. The increase in LF/HF preceded the increase in HF. In Group B, the baseline HF power spectrum and normalized values HFnu (HFnu = HF/LF + HF) were significantly increased in children older than 3 yr. Changes in HR induced by sevoflurane were negatively correlated with baseline HF and HFnu (R2 = 0.6; P < 0.001). These results demonstrate that withdrawal of parasympathetic tone is the main determinant for the change in HR induced by sevoflurane.
IMPLICATIONS: The effects of sevoflurane on parasympathetic activity could explain the difference in heart-rate changes described between infants and children during induction. This study describes the changes in heart rate and its variability induced by sevoflurane in children and shows that these changes are related to parasympathetic tone before the induction of anesthesia.

The Effect of Small Dose Fentanyl on the Emergence Characteristics of Pediatric Patients After Sevoflurane Anesthesia Without Surgery
Joseph P. Cravero, MD, Michael Beach, MD, Brian Thyr, MD, and Kate Whalen, RN
Anesth Analg 2003;97:364-367

We designed this study to measure the effect of a small dose of IV fentanyl on the emergence characteristics of pediatric patients undergoing sevoflurane anesthesia without any surgical intervention. Thirty-two ASA physical status I or II pediatric outpatients receiving sevoflurane anesthesia for magnetic resonance imaging scans were enrolled and assigned in a random and double-blinded manner to receive either placebo (saline) or 1 µg/kg IV fentanyl 10 min before discontinuation of their anesthetic. The primary outcome measure was the percentage of patients with emergence agitation. We also evaluated the duration of agitation and time to meet hospital discharge criteria. Patients who received fentanyl had a decreased incidence of agitation (12% versus 56%) when compared with placebo. There was no significant difference in time to meet hospital discharge criteria. We conclude that the addition of a small dose of fentanyl to inhaled sevoflurane anesthesia decreases the incidence of emergence agitation independent of pain control effects.
IMPLICATIONS: The addition of a small dose of fentanyl given to patients undergoing nonsurgical sevoflurane anesthesia resulted in a significant decrease in emergence agitation in a prospective, randomized, and controlled trial involving pediatric patients.

The Central Nervous System and Cardiovascular Effects of Levobupivacaine and Ropivacaine in Healthy Volunteers
Jonathan Stewart, MBChB, Norma Kellett, MBChB, and Dan Castro, MD
Anesth Analg 2003;97:412-416

We compared the central nervous system (CNS) and cardiovascular effects of levobupivacaine and ropivacaine when given IV to healthy male volunteers (n = 14) in a double-blinded, randomized, crossover trial. Subjects received levobupivacaine 0.5% or ropivacaine 0.5% after a test infusion with lidocaine to become familiar with the early signs of CNS effects (e.g., tinnitus, circumoral paresthesia, hypesthesia). The development of CNS symptoms was assessed at 1-min intervals and study drug administration was terminated when the first CNS symptoms were recognized. Thereafter, symptoms were recorded at 1-min intervals until symptom resolution. Hemodynamic variables were assessed by transthoracic electrical bioimpedance. Continuous 12-lead electrocardiogram monitoring was also performed. There was no significant difference between levobupivacaine and ropivacaine for: the mean time to the first onset of CNS symptoms (P = 0.870), mean total volume of study drug administered at the onset of the first CNS symptom (P = 0.595), stroke index (P = 0.678), cardiac index (P = 0.488), acceleration index (P = 0.697), PR interval (P = 0.213), QRS duration (P = 0.637), QT interval (P = 0.724), QTc interval (P = 0.737), and heart rate (P = 0.267). Overall, fewer CNS symptoms were reported for levobupivacaine than ropivacaine (218 versus 277). This study found that levobupivacaine and ropivacaine produce similar CNS and cardiovascular effects when infused IV at equal concentrations, milligram doses, and infusion rates.
IMPLICATIONS: This study compared directly, for the first time, the toxicity of levobupivacaine and ropivacaine in healthy volunteers. Levobupivacaine and ropivacaine produced similar central nervous system and cardiovascular effects when infused IV at equal concentrations, milligram doses, and infusion rates.

ANESTHESIOLOGY - TOP

Does the Routine Prophylactic Use of Antiemetics Affect the Incidence of Postdischarge Nausea and Vomiting following Ambulatory Surgery?: A Systematic Review of Randomized Controlled Trials
David C. Warltier, M.D., Ph.D., Editor; Anil Gupta, M.D., F.R.C.A., Ph.D.; Christopher L. Wu, M.D.; Nabil Elkassabany, M.D.; Courtney E. Krug, B.A., B.S.; Stephen D. Parker, M.D.; Lee A. Fleisher, M.D.
Anesthesiology 2003; 99(2):488-495

Meta-analysis of the literature showed that ondansetron 4 mg or combination treatment (> 1 drug) prevented postdischarge nausea and vomiting with a number needed to treat of 13 and 5, respectively.

Sacral Osteomyelitis after Single-shot Epidural Anesthesia via the Caudal Approach in a Child
Sabine Wittum, M.D.; Christoph K. Hofer, M.D., D.E.A.A.; Urs Rölli, M.D.; Markus Suhner, M.D.; Jacques Gubler, M.D.; Andreas Zollinger, M.D.
Anesthesiology 2003; 99(2):503-505

-- No abstract available --

Laryngeal Resistance before and after Minor Surgery: Endotracheal Tube versus Laryngeal Mask Airway™
Atsuko Tanaka, M.D.; Shiroh Isono, M.D.; Teruhiko Ishikawa, M.D.; Jiro Sato, M.D.; Takashi Nishino, M.D.
Anesthesiology 2003; 99(2):252-258

Background: The placement of an endotracheal tube (ETT) may promote laryngeal swelling, which is an important cause of upper airway obstruction after extubation. The authors hypothesized that laryngeal swelling after ETT placement increases laryngeal resistance and tested that hypothesis by comparing postoperative laryngeal patency between patients with ETT placement and those with a Laryngeal Mask AirwayTM (LMA^TM).
Methods: Fourteen adult patients who underwent elective minor surgeries were randomly allocated to two groups whose airway would be managed through ETTs (the ETT group) or LMAs^TM (the LMA^TMgroup) during the surgery. While maintaining at sevoflurane 1 minimum alveolar concentration, the authors measured laryngeal resistance before and after surgery, during both spontaneous breathing and mechanical ventilation under complete paralysis. In addition, they endoscopically measured the vocal cord angle under complete paralysis.
Results: In association with marked swelling of the vocal cords, the vocal cord angle significantly decreased after surgery in the ETT group, whereas the angle did not change in the LMA group. Laryngeal resistance during mechanical ventilation significantly increased only in the ETT group. Laryngeal resistance during spontaneous breathing significantly increased after surgeries in both groups.
Conclusions: Postoperative laryngeal resistance increases at least in part because of laryngeal swelling in patients with ETT placement, whereas alteration of laryngeal neural control mechanisms has been also indicated. The use of the LMA^TM has an advantage over ETT placement in order to avoid postoperative laryngeal swelling.

Is Routine Endotracheal Intubation as Safe as We Think or Wish? (Editorial)
Mazen A. Maktabi, M.D.; Russell B. Smith, M.D.; Michael M. Todd, M.D.
Anesthesiology 2003; 99(2):247-248

-- No abstract available --

ACTA ANAESTHESIOLOGICA SCANDINAVICA - TOP

Effects of adding epinephrine plus fentanyl to low-dose lidocaine for spinal anesthesia in outpatient knee arthroscopy
G. Türker, N. UÇkunkaya, A. Yilmazlar, B. Demiragand O. Tokat
Acta Anaesthesiologica Scandinavica Volume 47 Issue 8 Page 986

Background: This study investigated whether addition of 15 mcg epinephrine plus 25 mcg fentanyl to lidocaine spinal anesthesia for outpatient knee arthroscopy makes it possible to use a subanesthetic lidocaine dose. The aim was to assess the quality of anesthesia and the suitability of this protocol for outpatient knee arthroscopy.
Methods: Seventy-five outpatients scheduled for knee arthroscopy were randomly assigned to one of three spinal anesthetic protocols: Group L10F25 received 10 mg of lidocaine plus 25 mcg fentanyl; Group L10F25E15 received 10 mg of lidocaine plus 25 mcg fentanyl plus 15 mcg epinephrine; and Group L20F25 received 20 mcg lidocaine plus 25 mcg fentanyl. Tourniquet pain and surgical pain were assessed using a visual analog scale. If spinal anesthesia was inadequate despite supplementary intravenous analgesia and sedation, the patient was converted to general anesthesia. Recovery times and side-effects in the early postoperative period were recorded.
Results: The highest level of sensory block was above the T12 dermatome in all patients. Compared with the other groups, significantly more patients in Group L10F25 converted to general anesthesia. Group L10F25 had a significantly higher mean surgical pain score than the other groups. The mean tourniquet pain score was significantly higher in Group L20F25 than Group L10F25E15. Group L10F25E15 had a significantly shorter time to discharge than the other groups. Post-operative nausea and vomiting and drowsiness were more frequent in Group L10F25 than in the other groups.
Conclusion: The combination of 10 mg lidocaine and 25 mcg fentanyl plus 15 mcg epinephrine provides adequate spinal anesthesia and has favorable recovery characteristics for outpatient knee arthroscopy.

Automated responsiveness test and bispectral index monitoring during propofol and propofol/N₂O sedation
A. G. Doufas, M. Bakhshandeh, G. S. Haugh, A. R. Bjorksten, R. Greif and D. I. Sessler
Acta Anaesthesiologica Scandinavica Volume 47 Issue 8 Page 951

Background: Sedation practice, especially when non-anaesthesia personnel are involved, requires efficient anaesthetic depth monitoring. Therefore, we used prediction probability (PK) to evaluate the performance of the bispectral index (BIS) of the EEG and automated responsiveness test (ART) to predict sedation depth and loss of subject's responsiveness during propofol sedation, with and without N₂O.
Methods: Twenty volunteers were studied during propofol administration with (N₂O) and without (Air) N₂O. The protocol consisted of sequential 15-min cycles. After a control period, propofol was infused to a target effect-site concentration of 0.25 mcg/ml (N₂O) or 1.5 mcg/ml (Air), which was subsequently increased by 0.25 or 0.5 mcg/ml, respectively, until loss of responsiveness was detected by loss of response to command [observer's assessment of alertness/sedation (OAA/S) score 2].
Results: Deeply sedated patients did not respond to ART indicating that the sensitivity was 1.0 with or without N₂O. The specificity of ART was 0.24 with Air and 0.98 with N₂O. The BIS was better than ART in predicting OAA/S score (PK = 0.84 vs. 0.77) and loss of responsiveness (PK = 0.87 vs. 0.69) during the Air trial. Nitrous oxide decreased the performance of BIS in predicting OAA/S score (PK = 0.76), but increased the performance of ART to predict loss of responsiveness (PK = 0.85).
Conclusion: BIS and ART comparably predict sedation and loss of responsiveness. However, ART, because of its resistance to false-normal responses, might prove to be more useful on an individual patient basis - especially in the presence of agents that impair BIS sensitivity.

Relaxing intraoperative natural sound blunts haemodynamic change at the emergence from propofol general anaesthesia and increases the acceptability of anaesthesia to the patient
M. Tsuchiya, A. Asada, K. Ryo, K. Noda, T. Hashino, Y. Sato, E. F. Sato and M. Inoue
Acta Anaesthesiologica Scandinavica Volume 47 Issue 8 Page 939

Background: It is known that auditory input, such as comforting music or sound, blunts the human response to surgical stress in conscious patients under regional anaesthesia. As auditory perception has been demonstrated to remain active under general anaesthesia, playing comforting sounds to patients under general anaesthesia might also modulate the response of these patients to surgical stress.
Methods: Fifty-nine patients scheduled for laparoscopic cholecystectomy were anaesthetized with propofol general anaesthesia in combination with epidural anaesthesia. Natural sounds, chosen preoperatively by each patient as being comforting, were played to 29 patients using headphones during surgery (S group) and the remainder of the patients (n = 30) were fitted with dummy open-type headphones (N group). We compared the haemodynamic change during anaesthesia and the acceptability of anaesthetic practice between the two groups in a randomized double-blind design.
Results: There were no differences in haemodynamics between the S and N groups during surgery. During the emergence from anaesthesia, the mean blood pressure and heart rate gradually increased; both parameters were significantly higher in the N group than in the S group. Postoperatively, patients in the S group perceived the experience of anaesthesia as significantly more acceptable than did those in the N group.
Conclusion: These findings indicate that allowing patients comforting background sounds during general anaesthesia may blunt haemodynamic changes upon emergence from general anaesthesia and increase the acceptability of the experience of anaesthesia.

Patient-controlled regional analgesia (PCRA) with ropivacaine after arthroscopic subacromial decompression
K. Axelsson, U. Nordenson, E. Johanzon, N. Rawal, G. Ekbäck, G. Lidegran and A. Gupta
Acta Anaesthesiologica Scandinavica Volume 47 Issue 8 Page 993

Background: The aim of the study was to evaluate postoperative analgesia and safety of wound instillation of ropivacaine either by a single dose or a patient-controlled regional anaesthesia (PCRA) technique.
Methods: In 40 patients undergoing arthroscopic subacromial decompression the surgeon placed a catheter into the subacromial space at the end of the operation. In Phase I (10 patients), ropivacaine 250 mg was injected twice within 1 h. In Phase II, 30 patients were randomised into three groups: group prilocaine-ropivacaine (PR) = 20 ml of 1% prilocaine-epinephrine injected preoperatively into the subacromial bursa + 20 ml of 0.5% ropivacaine infused in the catheter postoperatively; group saline-ropivacaine (SR) = saline-epinephrine (20 ml) preoperatively + 0.5% ropivacaine as in group PR; group saline-saline (SS) = saline-epinephrine (20 ml) preoperatively + saline postoperatively. The PCRA pump was filled with local anaesthetic or saline to allow boluses of 10-ml each, maximum one bolus/h, via the catheter. Pain relief, side-effects and venous plasma concentration of ropivacaine were evaluated during a 24-h-test period.
Results: The free plasma concentration of ropivacaine was 0.12 + 0.041 mg l^-1 in Phase I. No adverse effects were seen. In Phase II pain at rest and on movement was lower in group PR than in group SS during the first 30 min postoperatively (P < 0.05). Group PR had the lowest morphine consumption (P < 0.05). Five to seven boluses were administered via the PCRA-pump, and 20 min after administration of the study solution, pain was lower in groups PR and SR compared with group SS (P < 0.001).
Conclusions: Preoperative intrabursal prilocaine with epinephrine + postoperative subacromial administration of ropivacaine by PCRA-technique provided the most effective analgesia with no major side-effects. The free plasma concentrations of ropivacaine were far below toxic concentrations.

Sevoflurane: an ideal agent for adult day-case anesthesia? (Review)
S. Ghatge, J. Lee and I. Smith
Acta Anaesthesiologica Scandinavica Volume 47 Issue 8 Page 917

Sevoflurane has several properties which make it potentially useful as a day case anaesthetic. Following induction of anaesthesia with propofol, awakening from sevoflurane is faster compared to isoflurane, faster or similar compared to propofol and comparable (in the majority of studies) to desflurane. Subsequent recovery and discharge is generally similar following all agents. Sevoflurane may also be used to induce anaesthesia, which is generally well-received and causes less hypotension and apnoea compared to propofol.
When used as a maintenance anaesthetic, the incidence of postoperative nausea and vomiting after sevoflurane is comparable to other inhaled anaesthetics, but this complication appears more common after inhaled inductions. The tolerability and low solubility of sevoflurane facilitate titration of anaesthesia and may reduce the need for opioid analgesia, which in turn may limit the occurrence of nausea and vomiting.

Intravenous clonidine prolongs bupivacaine spinal anesthesia
K. Rhee, K. Kang, J. Kim and Y. Jeon
Acta Anaesthesiologica Scandinavica Volume 47 Issue 8 Page 1001

Background: Prolongation of spinal anesthesia by oral clonidine premedication has been known. We hypothesized that intravenous clonidine administered after the spinal block may prolong spinal anesthesia.
Methods: To assess the prolongation of spinal anesthesia by intravenous clonidine, we designed a double-blind, placebo-controlled, prospective study. Patients scheduled for orthopedic surgery received 12 mg of 0.5% hyperbaric bupivacaine and were randomly divided into three groups (n = 26 in each group). In the clonidine 10-min group, 3 mcg kg^-1 of clonidine was administered for 10 min immediately after the spinal block. In the clonidine 60-min group, 3 mcg kg^-1 of clonidine was administered for 10 min, 50 min after the spinal block. The control group received normal saline. Sensory block was evaluated by pinprick and the duration was defined as the time for sensory block to regress to L1 dermatome. Duration of motor block was defined as the time required for the patient to flex his or her knee.
Results: The duration of sensory block was longer in both the clonidine 10-min and clonidine 60-min groups compared with the control group (196 ± 42 min, 179 ± 41 min vs. 125 ± 25 min, P < 0.05). The duration of motor block was longer in the clonidine 10-min group than in the control group (153 ± 26 min vs. 131 ± 29 min, P < 0.05). The lowest heart rate and mean blood pressure were not different among groups.
Conclusions: Intravenous clonidine administration within 1 h after the spinal block prolonged bupivacaine spinal anesthesia for approximately 1 h without adverse effects.

PUB MED - TOP

A comparison of the effect of two anaesthetic techniques on surgical conditions during gynaecological laparoscopy.
Williams MT, Rice I, Ewen SP, Elliott SM.
Anaesthesia. 2003 Jun;58(6):574-8.

In a prospective, randomised, controlled trial, we compared the effects of two anaesthetic techniques on surgical conditions during day-case, gynaecological laparoscopic procedures in 40 female patients. Patients were allocated randomly to two groups, either to breathe spontaneously through a laryngeal mask airway or to receive a neuromuscular-blocking agent (NMB) and have the lungs ventilated via a tracheal tube. We then measured the number of attempts of Verres' needle insertion, initial intra-abdominal pressure, time to reach a steady 15 mmHg (1.97 kPa) of intra-abdominal pressure, adequacy of the pneumoperitoneum, operative view and duration of operation. We found that the initial intra-abdominal pressure was higher and the operation time shorter in the laryngeal mask group. The adequacy of the pneumoperitoneum for trocar placement was better in the NMB group. We conclude that the anaesthetic technique of spontaneously breathing through a laryngeal mask airway reduces total operation time. However surgeons should be aware of the different abdominal pressure patterns produced by each anaesthetic technique, and anaesthetists must consider the implications of the anaesthetic technique on surgical safety.

State of the art of pain treatment following ambulatory surgery.
Chauvin M.
Eur J Anaesthesiol. 2003;20 Suppl 28:3-6.

BACKGROUND AND OBJECTIVE: The growth of ambulatory surgical procedures is limited by severe postoperative pain. After particularly painful operative procedures, moderate-to-severe pain is estimated to occur in approximately 30% of patients. Inadequate analgesia may delay or prevent discharge, or result in readmission. Severe postoperative pain also causes extreme discomfort and can prevent sleep, thus contributing to postoperative fatigue. Moreover, postoperative pain limits mobility at home and delays the return to normal activities. The development of effective analgesia for postoperative pain is therefore a priority of modern medicine.
RESULTS: The pain experienced during the first days spent at home is related to the magnitude of pain experienced at the hospital. Aggressive analgesic treatment at the hospital is therefore of key importance. This includes pre- and intraoperative administration of analgesics to reduce the pain in the immediate postoperative period, and the use of multimodal, balanced analgesia throughout recovery. Clinical studies have shown that patients who receive both pre- and postoperative analgesia experience greater pain relief than those who receive postoperative analgesia alone. Multimodal analgesia, including the use of anaesthetics, is increasingly important in attempts to avoid the prescription of single strong opioids postoperatively. The use of a non-steroidal anti-inflammatory drug (NSAID) plus an anaesthetic perioperatively has also been shown to be more effective than anaesthetic alone.
CONCLUSIONS: Postoperative pain is the most commonly reported complication of ambulatory surgery. Although the number of analgesic techniques seems more limited in outpatient than in inpatient surgery, the combination of analgesic regimens in a multimodal approach may improve postoperative analgesia and functional outcome after ambulatory surgery. The combination of acetaminophen plus tramadol is a useful formulation to prescribe if acetaminophen or NSAIDs alone are ineffective.

Day-case laparoscopic Nissen fundoplication.
Bailey ME, Garrett WV, Nisar A, Boyle NH, Slater GH.
Br J Surg. 2003 May;90(5):560-2.

BACKGROUND: The aim was to assess the acceptability and safety of day-case laparoscopic fundoplication for gastro-oesophageal reflux disease (GORD).
METHODS: This prospective study commenced in December 1999 and lasted for 18 months. All patients had proven symptomatic GORD. Inclusion criteria were American Society of Anesthesiologists grade I or II with adequate home support. A standard anaesthetic, analgesic and antiemetic protocol was used. Patients were contacted by telephone on the night of discharge and arrangements were made for a nurse to visit the following day. Postoperative pain and nausea were assessed using visual analogue scores (scale 0-10) on a self-completion questionnaire.
RESULTS: Twenty patients were included. There were no postoperative complications. All patients were discharged on the day of surgery. Median time to discharge was 6 h 30 min (range 4.5 to 9 h). One patient reattended casualty the following morning but none required readmission. There was no significant difference in median pain or nausea scores the evening after surgery or the next morning. All patients were satisfied with the information given and aftercare provided. All would recommend it to a friend and 19 of 20 would undergo the procedure as a day case again.
CONCLUSION: This study suggests that day-case laparoscopic fundoplication is feasible. Patients find it acceptable and it appears safe.

Anaesthesia for day case surgery: a survey of paediatric clinical practice in the UK.
Payne K, Moore EW, Elliott RA, Moore JK, McHugh GA.
Eur J Anaesthesiol. 2003 Apr;20(4):325-30

BACKGROUND AND OBJECTIVE: In October 2000, we conducted a national postal survey of day case consultant anaesthetists in the UK to explore the range and variation in practice of anaesthetizing a patient for day case surgery (paediatrics, urology and orthopaedics). This paper reports the findings of this national survey of paediatric day case anaesthetic practice carried out as part of a major two-centre randomized controlled trial designed to investigate the costs and outcome of several anaesthetic techniques during day care surgery in paediatric and adult patients (cost-effectiveness study of anaesthesia in day case surgery).
METHODS: The survey used a structured postal questionnaire and collected data on the duration of surgical procedure; the use of premedication; the anaesthetic agents used for induction and maintenance; the fresh gas flow rates used for general anaesthesia; the use of antiemetics; and the administration of local anaesthesia and analgesia.
RESULTS: The overall response rate for the survey was 74 and 63% for the paediatric section of the survey. Respondents indicated that 19% used premedication, 63% used propofol for induction, 54% used isoflurane for maintenance, 24% used prophylactic antiemetics and 85%, used a laryngeal mask. The findings of this national survey are discussed and compared with published evidence.
CONCLUSIONS: This survey identifies the variation in clinical practice in paediatric day surgery anaesthesia in the UK.

Anaesthesia for day case surgery: a survey of adult clinical practice in the UK.
Payne K, Moore EW, Elliott RA, Pollard BJ, McHugh GA.
Eur J Anaesthesiol. 2003 Apr;20(4):311-24.

BACKGROUND AND OBJECTIVE: In October 2000, we conducted a national postal survey of consultant day case anaesthetists in the UK to explore the range and variation in the practice of anaesthetizing a patient for day case surgery (paediatrics, urology and orthopaedics). The survey was carried out as part of a larger study that comprised a major two-centre randomized controlled trial designed to investigate the costs and outcome of several anaesthetic techniques during day care surgery in paediatric and adult patients (cost-effectiveness study of anaesthesia in day case surgery). We report the findings of this national survey of adult urology and orthopaedic day case anaesthetic practice in the UK.
METHODS: The survey used a structured postal questionnaire and collected data on the duration of the surgical procedure; the use of premedication; the anaesthetic agents used for induction and maintenance; the fresh gas flows used for anaesthesia; the use of antiemetics; and the administration of local anaesthesia and analgesia.
RESULTS: The overall response rate for the survey was 74% (63% for urology, 67% for orthopaedics). The survey indicated the following practice in adult urology and adult orthopaedic day case surgery: 6 and 12% used premedication; propofol was the preferred induction agent (96 and 97%) and isoflurane the preferred maintenance agent (56 and 58%); 32 and 41% used prophylactic antiemetics; 86 and 93% used a laryngeal mask.
CONCLUSIONS: This survey identifies the variation in current clinical practice in adult day surgery anaesthesia in the UK and discusses this variation in the context of current published evidence.

Clinical and economic choices in anaesthesia for day surgery: a prospective randomised controlled trial.
Elliott RA, Payne K, Moore JK, Harper NJ, St Leger AS, Moore EW, Thoms GM,
Pollard BJ, McHugh GA, Bennett J, Lawrence G, Kerr J, Davies LM.
Anaesthesia. 2003 May;58(5):412-21

We compared the cost-effectiveness of general anaesthetic agents in adult and paediatric day surgery populations. We randomly assigned 1063 adult and 322 paediatric elective patients to one of four (adult) or two (paediatric) anaesthesia groups. Total costs were calculated from individual patient resource use to 7 days post discharge. Incremental cost-effectiveness ratios were expressed as cost per episode of postoperative nausea and vomiting (PONV) avoided. In adults, variable secondary care costs were higher for propofol induction and propofol maintenance (propofol/propofol; p < 0.01) than other groups and lower in propofol induction and isoflurane maintenance (propofol/isoflurane; p < 0.01). In both studies, predischarge PONV was higher if sevoflurane/sevoflurane (p < 0.01) was used compared with use of propofol for induction. In both studies, there was no difference in postdischarge outcomes at Day 7. Sevoflurane/sevoflurane was more costly with higher PONV rates in both studies. In adults, the cost per extra episode of PONV avoided was 296 pounds (propofol/propofol vs. propofol/ sevoflurane) and 333 pounds (propofol/sevoflurane vs. propofol/isoflurane).

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