The Use of Esmolol as an Alternative to Remifentanil During Desflurane Anesthesia for Fast-Track Outpatient Gynecologic Laparoscopic Surgery

The effect of perioperative esmolol infusion on the postoperative nausea, vomiting and pain after laparoscopic appendectomy

BACKGROUND

Perioperative opioid administration results in postoperative nausea and vomiting (PONV) and acute opioid tolerance that manifests in increased postoperative pain. Esmolol is an ultra short acting cardioselective β1-adrenergic receptor antagonist, and it has been successfully used for perioperative sympatholysis and it reduces the opioid requirement during total intravenous anesthesia. We tested the hypothesis that perioperative esmolol administration results in decreased PONV and postoperative pain.

METHODS

Sixty patients undergoing laparoscopic appendectomy were randomly assigned to two groups (Group E and Group C). The Group E patients were administered 5-10 µg/kg/min esmolol with remifentanil that was titrated to the autonomic response. The Group C patients received normal saline that was of the same volume as the esmolol in Group E, and the remifentanil was also titrated to the vital sign. Before intubation and extubation, the Group E patients were administered 1.0 mg/kg esmolol, and the Group C patients were administered normal saline of the same volume. The incidence and severity of PONV, the pain score, the rescue antiemetics and the rescue analgesics were assessed 30 min, 6 h and 24 h after surgery. The mean arterial pressure and heart rate under anesthesia were also recorded.

RESULTS

PONV and postoperative pain were significantly increased in Group C. These patients needed more antiemetics and analgesics in the first 24 postoperative hours. The mean arterial pressure and heart rate were significantly higher in Group C at the time of intubation and extubation.

CONCLUSIONS

Perioperative esmolol administration contributes to the significant decrease in PONV and postoperative pain, and so this facilitates earlier discharge.

Postoperative pain management after ambulatory surgery: role of multimodal analgesia

Multimodal (or balanced) analgesia represents an increasingly popular approach to preventing postoperative pain. The approach involves administering a combination of opioid and nonopioid analgesics. Nonopioid analgesics are increasingly being used as adjuvants before, during, and after surgery to facilitate the recovery process after ambulatory surgery. Early studies evaluating approaches to facilitating the recovery process have demonstrated that the use of multimodal analgesic techniques can improve early recovery as well as other clinically meaningful outcomes after ambulatory surgery. The potential beneficial effects of local anesthetics, NSAIDs, and gabapentanioids in improving perioperative outcomes continue to be investigated.

Inhibitory effects of landiolol and nicardipine on thiopental-induced yawning in humans

PURPOSE

Either the calcium (Ca(2+))-channel blocker nicardipine or the beta(1)-adrenoceptor antagonist landiolol may be intravenously (IV) administered to reduce the hemodynamic responses to tracheal intubation. In this study, we examined the effects of these drugs on the yawning response elicited by intravenous thiopental in humans.

METHODS

After Institutional Review Board approval, 180 consenting American Society of Anesthesiologists (ASA) I or II patients undergoing elective surgery were recruited. In a double-blind, randomized design, three groups of 60 patients each received one of the following intravenous injections: (1) landiolol 0.1 mg/kg (L-group), (2) nicardipine 0.02 mg/kg (N-group), or (3) saline (S-group). In all patients, anesthesia was subsequently induced IV with 4 mg/kg thiopental. Thereafter, the occurrence of the yawning response (characterized by mouth opening) was continuously assessed as the only clinical endpoint for 1 min. Throughout the study, mean arterial blood pressure and heart rate were also recorded at 1-min intervals.

RESULTS

The incidence of the yawning response was lower in both the L-group (6.7%) and the N-group (16.7%) than in the S-group (46.7%) (each, P < 0.01).

CONCLUSIONS

Prior intravenous administration of either a Ca(2+)-channel blocker or a beta(1)-adrenoceptor antagonist can greatly reduce the thiopental-induced yawning response in humans.

Landiolol, a new ultra-short-acting beta1-blocker, reduces anaesthetic requirement during sevoflurane/N(2)O/fentanyl anaesthesia in surgical patients

BACKGROUND AND OBJECTIVE

It is known that esmolol, a short-acting beta1-blocker, reduces anaesthetic requirement. In this study, we evaluated whether a low dose of landiolol, a new ultra-short-acting beta1-blocker, can reduce the sevoflurane requirement.

METHODS

Twenty-five patients undergoing hip surgery were randomly divided into two groups. Group A (n = 13) received landiolol (bolus injection of 0.031 mg.kg(-1) and continuous infusion at a rate of 0.01 mg.kg(-1).min(-1)). Group B (n = 12) received physiological saline. Landiolol and physiological saline were started before the induction of anaesthesia and continued until the end of anaesthesia. Anaesthesia was maintained with sevoflurane, 60% N(2)O and fentanyl. Sevoflurane concentration was controlled to keep the bispectral index at approximately 50. The end-tidal sevoflurane concentration and haemodynamics were measured during anaesthesia.

RESULTS

The average end-tidal sevoflurane concentration in group A was significantly lower than that in group B (1.2 +/- 0.30 vs. 1.8 +/- 0.3%, P < 0.01). Maximum values of systolic arterial pressure showed no difference between the groups, whereas the maximum value of heart rate in group A was significantly less than that in group B (61 +/- 10 vs. 76 +/- 14 beats min(-1), P < 0.05).

CONCLUSION

The results suggest that a low dose of landiolol significantly reduces the intraoperative sevoflurane requirement during sevoflurane/N(2)O/fentanyl anaesthesia in patients undergoing hip surgery.

Both clonidine and metoprolol modify anesthetic depth indicators and reduce intraoperative propofol requirement

PURPOSE

Beta-blockers have been used in the past to decrease the depth of anesthesia, but the results are conflicting. However, beta-blockers are known to suppress electroencephalographic activities. This study was carried out to assess the effect of metoprolol on anesthetic depth indicators. We also compared the effect of metoprolol in reducing propofol requirements.

METHODS

Ninety healthy adult patients undergoing peripheral nerve injury repair were enrolled in three groups to receive either: a tablet containing clonidine 200 microg, a tablet containing metoprolol tartrate 100 mg, or a placebo; 1 h prior to surgery. Standard anesthesia technique was followed. The bispectral index was monitored to guide propofol infusion and was maintained between 40 and 60. The total duration of anesthesia and surgery, and the total propofol consumption, were noted.

RESULTS

Demographic variables were comparable in all three groups. Significantly less propofol was consumed by patients in the clonidine and metoprolol groups in comparison to that in the placebo group (P < 0.001). Heart rate and mean blood pressure values differed significantly in the placebo group in comparison to the values in the other two groups.

CONCLUSION

Our study showed that, like clonidine, metoprolol attenuated the hemodynamic response to intraoperative stimuli and also had a sparing effect on the propofol dose requirement.

Fast-track anesthetic techniques for ambulatory surgery

PURPOSE OF REVIEW

Improving perioperative efficiency and throughput has become increasingly important in facilitating the fast-track recovery process following ambulatory surgery. This review focuses on the important role played by the anesthesiologist as a perioperative physician in fast-track ambulatory surgery.

RECENT FINDINGS

A literature review of more than 200 peer-reviewed publications was used to develop evidence-based recommendations for optimizing recovery following ambulatory anesthesia. The choice of anesthetic technique should be tailored to the needs of the patient as well as the type of surgical procedure being performed in the ambulatory setting. The anesthetic decisions made by the anesthesiologist, as a key perioperative physician, are of critical importance in developing a successful fast-track ambulatory surgery program.

SUMMARY

The pivotal role played by the anesthesiologist as the key perioperative physician in facilitating the recovery process has assumed increased importance in the current outpatient fast-track recovery environment. The choice of premedication, anesthetic, analgesic and antiemetic drugs, as well as cardiovascular, hormonal and fluid therapies, can all influence the ability to fast-track outpatients after ambulatory surgery.

Labetalol facilitates GABAergic transmission to rat periaqueductal gray neurons via antagonizing beta1-adrenergic receptors--a possible mechanism underlying labetalol-induced analgesia

Labetalol, a combined alpha1, beta1, and beta2 adrenoceptor-blocking drug, has been shown to have analgesic properties in vivo. To determine the underlying mechanisms, we examined its effects on GABAA receptor-mediated spontaneous inhibitory postsynaptic currents (sIPSCs) and spontaneous firings of rat ventrolateral periaqueductal gray (PAG) neurons, either mechanically dissociated, or in acute brain slices. These PAG neurons mediate opioid-mediated analgesia and pain transmission and are under tonic control of GABAergic interneurons. An increase in GABAergic transmission to these neurons yields an inhibitory hyperpolarized state and may interrupt pain signal transmission. Using patch clamp techniques, we found that labetalol reversibly increases the frequency of sIPSCs without changing their mean amplitude. This indicates that labetalol enhances GABAergic synaptic transmission by a presynaptic mechanism. Metoprolol, a specific beta1-adrenoceptor antagonist, also reversibly enhanced sIPSC frequency. In the presence of metoprolol, labetalol-induced increase in sIPSC frequency was significantly attenuated or even abolished. These results suggest that labetalol shares the same pathway as metoprolol in enhancing GABAergic transmission via an inhibition of presynaptic beta1-adrenoceptors. We further showed that labetalol reversibly reduced the firing rate of PAG neurons. This reduction was significantly attenuated in the presence of bicuculline, a selective antagonist of GABAA receptors. These data indicate that labetalol-induced inhibition of PAG cell firing is attributable to its potentiation of GABAergic transmission. Based on these data, we postulate that labetalol-induced analgesia is at least in part ascribed to its antagonistic effects on presynaptic beta1-adrenoceptors.

Landiolol, an Ultra–Short-Acting β1-Adrenoceptor Antagonist, Does Not Alter the Minimum Alveolar Anesthetic Concentration of Isoflurane in a Swine Model

BACKGROUND

We previously reported that landiolol, an ultra-short-acting beta1-adrenoceptor antagonist, does not alter the electroencephalographic effect of isoflurane. Here, we investigated the influence of landiolol on the minimum alveolar anesthetic concentration (MAC) of isoflurane required to prevent movement in response to a noxious stimulus in 50% of subjects.

METHODS

Ten swine (29.0 +/- 3.4 kg) were anesthetized by inhalation of isoflurane. MAC was determined using the dewclaw clamp technique, in which movement in response to clamping is recorded. After determination of MAC in the baseline period, an infusion of landiolol (0.125 mg x kg(-1) x min(-1) for 1 min, then 0.04 mg x kg(-1) x min(-1)) was started. After a 20-min stabilization period, MAC was again assessed (0.04 mg x kg(-1) x min(-1) landiolol). The infusion of landiolol was then increased from 0.04 to 0.2 mg x kg(-1) x min(-1), and after a 20-min stabilization period, MAC was again assessed (0.2 mg x kg(-1) x min(-1) landiolol). Finally, the infusion of landiolol was stopped, and after a 20-min stabilization period, MAC was assessed for a fourth time (Baseline 2).

RESULTS

Landiolol clearly attenuated the increases in heart rate and mean arterial blood pressure that occurred in response to the dewclaw clamp, but did not alter the MAC of isoflurane.

CONCLUSIONS

Landiolol does not alter the antinociceptive effect of isoflurane. This result, combined with that from our previous work, also suggests that landiolol does not influence the anesthetic potency of inhaled anesthetics.

Anesthesia for outpatient gynecologic surgery

PURPOSE OF REVIEW

Anesthesia care for patients undergoing ambulatory gynecologic surgery has improved incrementally over the past few years. Emphasis has evolved beyond the safe provision of care, because this has largely been achieved. Comfort, speed, and efficiency have taken on new importance.

RECENT FINDINGS

Many changes relate to improvements in non-narcotic analgesic techniques and use of various supralaryngeal airways, such as the ProSeal LMA. Also, use of depth of anesthesia monitors and administration of potent short-acting beta-blockers and narcotics to control hemodynamic variables are examples of new anesthesia developments well applied to ambulatory gynecologic cases. Finally, anesthesia care is changing in some instances because surgical techniques are advancing, such as hysteroscopy, and can now be done in an office with little or no anesthesia.

SUMMARY

Local anesthetic use in gynecologic laparoscopy appears to improve postoperative pain control modestly, especially when given into the peritoneal cavity. Supralaryngeal airways, such as ProSeal LMA, appear to provide effective ventilation in laparoscopy, although their ability to protect against aspiration is unclear. The speed and comfort of emergence, recovery, and discharge may be improved by consciousness monitoring during general anesthesia and by drugs intended to modulate hemodynamics.

The Role of the Anesthesiologist in Fast-Track Surgery: From Multimodal Analgesia to Perioperative Medical Care

BACKGROUND

Improving perioperative efficiency and throughput has become increasingly important in the modern practice of anesthesiology. Fast-track surgery represents a multidisciplinary approach to improving perioperative efficiency by facilitating recovery after both minor (i.e., outpatient) and major (inpatient) surgery procedures. In this article we focus on the expanding role of the anesthesiologist in fast-track surgery.

METHODS

A multidisciplinary group of clinical investigators met at McGill University in the Fall of 2005 to discuss current anesthetic and surgical practices directed at improving the postoperative recovery process. A subgroup of the attendees at this conference was assigned the task of reviewing the peer-reviewed literature on this topic as it related to the role of the anesthesiologist as a perioperative physician.

RESULTS

Anesthesiologists as perioperative physicians play a key role in fast-track surgery through their choice of preoperative medication, anesthetics and techniques, use of prophylactic drugs to minimize side effects (e.g., pain, nausea and vomiting, dizziness), as well as the administration of adjunctive drugs to maintain major organ system function during and after surgery.

CONCLUSION

The decisions of the anesthesiologist as a key perioperative physician are of critical importance to the surgical care team in developing a successful fast-track surgery program.

Surgical stress index reflects surgical stress in gynaecological laparoscopic day-case surgery

BACKGROUND

Monitoring of analgesia remains a challenge during general anaesthesia. The surgical stress index (SSI) is derived from the photoplethysmographic waveform amplitude and the heart beat-to-beat interval. We evaluated the ability of SSI to measure surgical stress in patients undergoing gynaecological laparoscopy. Our hypothesis was that while keeping State Entropy (SE) at a predetermined level, SSI would be higher in patients receiving a beta-blocking agent (esmolol) than in those receiving an opioid (remifentanil) during laparoscopy.

METHODS

Thirty women undergoing gynaecological laparoscopy were assigned randomly to receive esmolol (n = 15) or remifentanil (n = 15). Anaesthesia was induced with propofol and fentanyl and maintained with desflurane and nitrous oxide 50% in oxygen to keep SE at 50(5). The infusion of esmolol or remifentanil was started before laparoscopy and adjusted to keep the systolic blood pressure at -20 to +10% from the preoperative value.

RESULTS

During the fentanyl phase, before surgery, both groups behaved similarly, with an increase in SSI after intubation. In the patients receiving esmolol, the SSI reacted to the initial incision (P < 0.05), and remained high after trocar insertion (P < 0.05). In patients receiving remifentanil, it did not react to the initial incision, but increased after trocar insertion (P < 0.05), and it remained lower both after incision (P < 0.05) and after trocar insertion (P < 0.05).

CONCLUSION

SSI was higher in patients receiving esmolol. The index seems to reflect the level of surgical stress and may help guide the use of opioids during general anaesthesia.

Nitrous oxide in ambulatory anaesthesia: does it have a place in day surgical anaesthesia or is it just a threat for personnel and the global environment?

PURPOSE OF REVIEW

Nitrous oxide is by far the oldest anaesthetic still in routine use and its continued use is often questioned. Nitrous oxide is toxic with prolonged exposure, can damage the environment, causes pressure effects through expansion of closed air-filled spaces and has long been suspected of being harmful following chronic exposure to trace concentrations. What could possibly justify the continuing use of nitrous oxide?

RECENT FINDINGS

This review will attempt to demonstrate that the harmful effects of nitrous oxide are limited and not relevant to the majority of ambulatory patients. The environmental effects of nitrous oxide derived from anaesthetic use are negligible and there is no convincing evidence of harm to personnel.

SUMMARY

Not only is nitrous oxide almost certainly less hazardous than is sometimes perceived, it has numerous benefits which are not easily replicated by possible alternatives. In particular, its use improves the quality and safety of induction and maintenance of anaesthesia and facilitates faster recovery with minimal adverse effects. All of these benefits are achieved while at the same time reducing overall costs. With few significant drawbacks and numerous advantages, there appears still to be a valuable place for nitrous oxide in modern ambulatory anaesthesia.

Landiolol, an ultra-short-acting beta 1-adrenoceptor antagonist, does not alter the electroencephalographic effect of isoflurane in swine model

BACKGROUND

beta-Adrenergic blocking agents may interact with anaesthetics, and several studies suggest that beta-blockers attenuate electroencephalographic responses during general anaesthesia. We have investigated the influence of landiolol, an ultra-short-acting beta 1-adrenoceptor antagonist, on the electroencephalographic effect of isoflurane in pigs.

METHODS

Ten swine were anaesthetized through inhalation of 2% isoflurane. The inhalational concentration was then decreased to 0.5% and maintained for 25 min, before being returned to 2% and maintained for a further 25 min (control period). After control measurements, infusion of landiolol (at 0.125 mg kg(-1) min(-1) for 1 min, and then at 0.04 mg kg(-1) min(-1)) was started. After a 20 min stabilization period, the inhalational concentration was varied as in the control period (40 gamma landiolol). Finally, infusion of landiolol was increased from 0.04 to 0.2 mg kg(-1) min(-1), and after a 20 min stabilization period, the inhalational concentration was again varied as in the control period (200 gamma landiolol). End-tidal isoflurane concentrations and spectral edge frequencies were recorded throughout the study. Analysis of the pharmacodynamics was performed using a sigmoidal inhibitory maximal effect model for spectral edge frequency vs effect-site concentration.

RESULTS

There were no significant differences in the effect of isoflurane among the conditions used. Landiolol did not shift the concentration-effect relationship [the effect-site concentration that produced 50% of the maximal effect was 1.35 (0.17)% under control conditions, 1.30 (0.12)% at 40 gamma landiolol, and 1.38 (0.30)% at 200 gamma landiolol].

CONCLUSION

Landiolol does not alter the electroencephalographic effect of isoflurane.

The changing role of non-opioid analgesic techniques in the management of postoperative pain

Given the expanding role of ambulatory surgery and the need to facilitate an earlier hospital discharge, improving postoperative pain control has become an increasingly important issue for all anesthesiologists. As a result of the shift from inpatient to outpatient surgery, the use of IV patient-controlled analgesia and continuous epidural infusions has steadily declined. To manage the pain associated with increasingly complex surgical procedures on an ambulatory or short-stay basis, anesthesiologists and surgeons should prescribe multimodal analgesic regimens that use non-opioid analgesics (e.g., local anesthetics, nonsteroidal antiinflammatory drugs, cyclooxygenase inhibitors, acetaminophen, ketamine, alpha 2-agonists) to supplement opioid analgesics. The opioid-sparing effects of these compounds may lead to reduced nausea, vomiting, constipation, urinary retention, respiratory depression and sedation. Therefore, use of non-opioid analgesic techniques can lead to an improved quality of recovery for surgical patients.

Response Entropy is not more sensitive than State Entropy in distinguishing the use of esmolol instead of remifentanil in patients undergoing gynaecological laparoscopy

BACKGROUND

Monitoring of analgesia remains a challenge during general anaesthesia. Activation of Response Entropy (RE) to painful stimuli has been suggested to be a sign of inadequate analgesia. We evaluated the ability of RE to be more sensitive than State Entropy (SE) in measuring nociception in patients undergoing gynaecological laparoscopy. Our hypothesis was that while keeping SE at a predetermined level, RE would be higher in patients receiving a beta-blocking agent (esmolol) instead of an opioid (remifentanil) during a propofol/nitrous oxide anaesthesia.

METHODS

Fifty-one women aged between 22-53 years were randomly assigned to receive esmolol (n=25) or remifentanil (n=26). SE was kept at 50+/-5. RE and SE were recorded at an interval of 30 s to 2 min and the areas under the RE and SE value-time curves (AUCRE and AUCSE) were calculated during the time of intubation and start of surgery as well as during the entire anaesthesia. The difference between RE and SE recordings in both groups was determined by subtracting the AUCSE from the corresponding AUCRE. Movements of the patients were recorded.

RESULTS

No significant differences were detected in any of the several AUC values between the groups. The difference between RE and SE recordings was similar in both groups. Every patient in the esmolol group moved some time during the procedure interfering with surgery while no one in the remifentanil group moved.

CONCLUSION

In patients undergoing gynaecological laparoscopic day-case surgery, RE seems not to be more sensitive than SE in guiding the use of opioids during general anaesthesia.

Role of β-blockade in anaesthesia and postoperative pain management after hysterectomy

BACKGROUND

Perioperative use of beta-blockers has been advocated as a strategy to prevent cardiac sequelae. This study evaluated the influence of perioperative esmolol administration upon anaesthesia and postoperative pain management amongst patients undergoing hysterectomy.

METHODS

Ninety-seven ASA I-II patients, undergoing abdominal total hysterectomy, were randomly divided into one of two groups. Patients in the Esmolol group received an i.v. loading dose of esmolol 0.5 mg kg(-1) followed by infusion of 0.05 mg kg(-1) min(-1) before anaesthesia induction. The infusion was documented at the completion of surgery. The Control group received a volume of normal saline. After surgery, all patients were treated with patient-controlled i.v. analgesia (PCA), which was programmed to deliver 1 mg of morphine on demand for 3 consecutive days. Pain intensity on movement and at rest, sedation score, and side effects were recorded.

RESULTS

The two groups were comparable with respect to their characteristics. Patients in the esmolol group received significantly lower end-tidal isoflurane concentrations (1.0 (0.3) vs 1.4 (0.5)%, respectively; P<0.001) and fentanyl (0.9 (0.2) vs 1.2 (0.5) microg kg(-1), respectively; P=0.006) during anaesthesia. They also showed a reduced heart rate and arterial pressure response to tracheal intubation, skin incision, and tracheal extubation. The Esmolol group consumed less PCA morphine in 3 days (37.3 (8.4) vs 54.7 (11.2) mg, respectively; P=0.005). Pain intensity and medication side effects were similar in the two groups.

CONCLUSION

The results suggest that perioperative esmolol administration during anaesthesia reduces the intraoperative use of inhalation anaesthetic and fentanyl, decreases haemodynamic responses, and reduced morphine consumption for the first 3 postoperative days.

Fast-tracking (bypassing the PACU) does not reduce nursing workload after ambulatory surgery †

BACKGROUND

Postoperative day-case patients are usually allowed to recover from anaesthesia in a postanaesthesia care unit (PACU) before transfer back to the day surgical unit (DSU). Bypassing the PACU can decrease recovery time after day surgery. Cost savings may result from a reduced nursing workload associated with the decreased recovery time. This study was designed to evaluate the effects of bypassing the PACU on patient recovery time and nursing workload and costs.

METHODS

Two hundred and seven consenting outpatients undergoing day surgery procedures were enrolled. Anaesthesia was induced and maintained with a standardized technique and the electroencephalographic bispectral index was monitored and maintained at 40-60 during anaesthetic maintenance. At the end of surgery, patients were randomly assigned to either a routine or fast-tracking (FT) group. Patients in the FT group were transferred from the operating room to the DSU (i.e. bypassing the PACU) if they achieved the FT criteria. All other patients were transferred to the PACU and then to the DSU. Nursing workload was evaluated using a patient care hour chart based on the type and frequency of nursing interventions in the PACU and DSU. A cost associated with the nursing workload was calculated.

RESULTS

The overall time from end of anaesthesia to discharge home was significantly decreased in the fast-tracking group. However, overall patient care hours and costs were similar in the two recovery groups.

CONCLUSION

Bypassing the PACU after these short outpatient procedures significantly decreases recovery time without compromising patient satisfaction. However, the overall nursing workload and the associated cost were not significantly affected.

PACU fast-tracking: an alternative to "bypassing" the PACU for facilitating the recovery process after ambulatory surgery

This retrospective evaluation assessed the impact of discharging outpatients home directly from the PACU as an alternative to "PACU bypassing." A total of 1,380 outpatients who had undergone minor ambulatory procedures were evaluated. Nine hundred fifty-two outpatients were admitted to a designated PACU fast-tracking area to facilitate an earlier discharge. Of the outpatients admitted to the PACU fast-track area, 88% were discharged home within 60 minutes (mean time [+/- SD] of 58 +/- 8 minutes]. The remaining 12% were discharged home from the PACU in an average of 88 (+/- 12) minutes. The recovery times for the 428 outpatients who were initially considered for the PACU fact-tracking program but were admitted to the regular PACU and recovered according to the conventional (two-step) pathway were 38 +/- 25 minutes in the PACU, followed by 61 +/- 32 minutes in the day surgery step-down unit. We conclude that this pilot program demonstrates the feasibility of discharging patients home from the PACU. Only 12% of the outpatients who were admitted to the PACU fast-track area failed to be discharged within 60 minutes. The overall times to discharge from the PACU fast-track area compared favorably to discharge times for outpatients bypassing the PACU. This program provides nurses with an alternative recovery pathway for fast-tracking patients after ambulatory surgery.

Esmolol prevents movement and attenuates the BIS response to orotracheal intubation

BACKGROUND

Beta-adrenergic agonists enhance behavioural and electroencephalographic arousal reactions. We explored whether adding esmolol, a short-acting beta(1)-adrenoceptor antagonist, to propofol anaesthesia modified the bispectral index (BIS) during induction of anaesthesia and orotracheal intubation.

METHODS

Fifty patients were randomly allocated, in a double-blind fashion, to receive esmolol 1 mg kg(-1) followed by 250 micro g kg(-1) min(-1) or saline (control). Esmolol or saline was started 6 min after a target-controlled infusion (TCI) of propofol (effect-site concentration 4 micro g ml(-1)). After loss of consciousness, and before administration of vecuronium 0.1 mg kg(-1), a tourniquet was applied to one arm and inflated to 150 mm Hg greater than systolic pressure. Eleven minutes after the TCI began, the trachea was intubated; gross movement within the first min after orotracheal intubation was recorded. BIS was recorded at 10-s intervals. Mean arterial pressure (MAP) and heart rate were measured non-invasively every min.

RESULTS

There were no intergroup differences in BIS, heart rate or MAP before laryngoscopy. BIS increased significantly after orotracheal intubation (compared with the pre-laryngoscopy values) in the control group only, with a maximum increase of 40 (SD 18)% vs 8 (11)% in the esmolol group (P<0.01). Maximum changes in heart rate [45 (19)% vs 23 (14)%] and MAP [62 (24)% vs 45 (23)%] with orotracheal intubation were also significantly greater in the control group than in the esmolol group. More patients in the control than in the esmolol group moved after orotracheal intubation (23 vs 12, P<0.01).

CONCLUSION

Esmolol not only attenuated haemodynamic and somatic responses to laryngoscopy and orotracheal intubation, but also prevented BIS arousal reactions in patients anaesthetized with propofol.

Esmolol and anesthetic requirement for loss of responsiveness during propofol anesthesia

The administration of esmolol decreases the propofol blood concentration, preventing movement after skin incision during propofol/morphine/nitrous oxide anesthesia. However, interaction with esmolol has not been tested when propofol is infused alone. Accordingly, we tested the hypothesis that esmolol decreases the propofol blood concentration, preventing response to command (CP50-awake) when propofol is infused alone in healthy patients presenting for minor surgery. With approval and consent, we studied 30 healthy patients, who were randomized to esmolol bolus (1 mg/kg) and then infusion (250 microg x kg(-1) x min(-1)) or placebo. Five minutes later, a target-controlled infusion of propofol was commenced. Ten minutes later, responsiveness was assessed by a blinded observer. Oxygen saturation, heart rate, and noninvasive arterial blood pressure were recorded every 2 min. Arterial blood samples were taken at 5 and 10 min of propofol infusion for propofol assay. Results were analyzed with a generalized linear regression model: P <0.05 was considered statistically significant. The probability of response to command decreased with increasing propofol blood concentration (CP50-awake = 3.42 microg/mL). Esmolol did not alter the relative risk of response to command. We conclude that the previously observed effect of esmolol on propofol CP50 was not caused by an interaction between these two drugs.

IMPLICATIONS

There is no evidence to suggest that esmolol, an ultra-short-acting cardioselective beta-blocker, affects anesthetic requirement for loss of responsiveness during propofol anesthesia.

Fast-tracking after ambulatory surgery

The fast-tracking recovery concept examines different paradigms for streamlining the postoperative recovery process. Fast-tracking anesthetic techniques allow suitable outpatients to be discharged earlier after ambulatory surgery. Outpatients are normally transferred from the OR to the PACU, followed by transfer to the Phase II step-down (day-surgery unit) before discharge home. With conventional fast-tracking, it is possible to bypass the PACU and take patients directly from the OR to the step-down unit if they meet specific criteria before leaving the OR. Alternatively, if the step-down unit is already functioning at maximum capacity, the PACU can be restructured to include a fast-track area, where appropriate patients are treated as if they had been admitted directly to the step-down unit. For these PACU fast-track patients, less monitoring is performed, a family member is permitted to be with the patient, and the patient is allowed to ambulate, change into street clothes, and be discharged home directly from the PACU without any time restrictions. Preliminary studies have shown that outpatients who are fast-tracked can be discharged home earlier without any increase in complications or side effects. Importantly, fast-tracking after ambulatory surgery does not seem to compromise patient satisfaction with the surgical experience.

A comparative study of general anesthesia, intravenous regional anesthesia, and axillary block for outpatient hand surgery: clinical outcome and cost analysis

IV regional anesthesia can offer a more favorable patient recovery profile and shorter postoperative nursing care time and hospital discharge time than an isoflurane-based general anesthetic or brachial plexus block technique for hand surgery.

Fast-tracking after outpatient laparoscopy: reasons for failure after propofol, sevoflurane, and desflurane anesthesia

IMPLICATIONS

In this study, although 41%-94% of the patients were fast-track eligible after laparoscopic surgery, only 35%-53% of the patients actually bypassed the postanesthesia care unit (PACU) because of anesthetic-related factors and surgical complications. Residual sedation was the most common anesthetic-related cause of failure to bypass thePACU.