Postanesthesia Care Unit Admission Research Articles

Intraoperative Acceleromyographic Monitoring Reduces the Risk of Residual Neuromuscular Blockade and Adverse Respiratory Events in the Postanesthesia Care Unit

Incomplete recovery from neuromuscular blockade in the postanesthesia care unit (PACU) may contribute to adverse postoperative respiratory events. This study determined the incidence and degree of residual neuromuscular blockade in patients randomized to conventional qualitative train-of-four (TOF) monitoring or quantitative acceleromyographic monitoring. The incidence of adverse respiratory events in the PACU was also evaluated. One hundred eighty-five patients were randomized to intraoperative acceleromyographic monitoring (acceleromyography group) or qualitative TOF monitoring (TOF group). Anesthetic management was standardized. TOF patients were extubated when standard criteria were met and no fade was observed during TOF stimulation. Acceleromyography patients had a TOF ratio of greater than 0.80 as an additional extubation criterion. Upon arrival in the PACU, TOF ratios of both groups were measured with acceleromyography. Adverse respiratory events during transport to the PACU and during the first 30 min of PACU admission were also recorded. A lower frequency of residual neuromuscular blockade in the PACU (TOF ratio < or = 0.9) was observed in the acceleromyography group (4.5%) compared with the conventional TOF group (30.0%; P < 0.0001). During transport to the PACU, fewer acceleromyography patients developed arterial oxygen saturation values, measured by pulse oximetry, of less than 90% (0%) or airway obstruction (0%) compared with TOF patients (21.1% and 11.1%, respectively; P < 0.002). The incidence, severity, and duration of hypoxemic events during the first 30 min of PACU admission were less in the acceleromyography group (all P < 0.0001). Incomplete neuromuscular recovery can be minimized with acceleromyographic monitoring. The risk of adverse respiratory events during early recovery from anesthesia can be reduced by intraoperative acceleromyography use.

Residual Neuromuscular Blockade and Critical Respiratory Events in the Postanesthesia Care Unit

Incomplete recovery of neuromuscular function may impair pulmonary and upper airway function and contribute to adverse respiratory events in the postanesthesia care unit (PACU). The aim of this investigation was to assess and quantify the severity of neuromuscular blockade in patients with signs or symptoms of critical respiratory events (CREs) in the PACU. We collected data over a 1-yr period. PACU nurses identified patients with evidence of a predefined CRE during the first 15 min of PACU admission. Train-of-four (TOF) ratios were immediately quantified in these patients using acceleromyography (cases). TOF data were also collected in a control group that consisted of patients undergoing a general anesthetic during the same period who were matched with the cases by age, sex, and surgical procedure. A total of 7459 patients received a general anesthetic during the 1-yr period, of whom 61 developed a CRE. Forty-two of these cases were matched with controls and constituted the study group for statistical analysis. The most common CREs among matched cases were severe hypoxemia (22 of 42 patients; 52.4%) and upper airway obstruction (15 of 42 patients; 35.7%). There were no significant differences between the cases and matched controls in any measured preoperative or intraoperative variables. Mean (+/-sd) TOF ratios were 0.62 (+/-0.20) in the cases, with 73.8% of the cases having TOF ratios <0.70. In contrast, TOF values in the controls were 0.98 (+/-0.07) (a difference of -0.36 with a 95% confidence interval of -0.43 to -0.30, P < 0.0001), and no control patients were observed to have TOF values <0.70 (the 95% confidence interval of the difference was 59%-85%, P < 0.0001). A high incidence of severe residual blockade was observed in patients with CREs, which was absent in control patients without CREs. These findings suggest that incomplete neuromuscular recovery is an important contributing factor in the development of adverse respiratory events in the PACU.

Comparison of two convective warming systems during major abdominal and orthopedic surgery

Convective warming is routinely employed to maintain perioperative normothermia. However, due to differences in nozzle temperature and air flow of the power units, there are clinically relevant differences in heat transfer among convective warming systems. The purpose of this study was to evaluate the use of a quieter, convective warming system (WarmAir, sound pressure level 49 dba, air flow 35 cfm). The WarmAir system was compared to the standard, higher air flow system (Bair Hugger Model 750, sound pressure level 55 dba, air flow 48 cfm) with regards to temperature outcome. Patients undergoing general anesthesia for major abdominal and orthopedic surgery were randomized into one of two groups: WarmAir or Bair Hugger. Both groups received an upper body, convective blanket using coverage appropriate for the given surgical procedure. Convective warming, at the high setting, was started after prepping and draping, and distal esophageal or nasopharyngeal temperature was measured intraoperatively. Sublingual temperature was measured preoperatively and on admission to the postanesthesia care unit. The WarmAir (n = 89) and Bair Hugger (n = 95) groups were similar with respect to age, gender, body mass index, ASA status, fluid balance, and duration of surgery. There was no difference in temperature outcomes between groups. In the WarmAir group, preoperative, lowest intraoperative, end of surgery, and postanesthesia care unit admission temperatures were (means +/- SD); 36.3 +/- 0.5, 35.4 +/- 1.1, 36.4 +/- 0.7, and 36.4 +/- 0.6 degrees C, respectively. Corresponding temperatures in the Bair Hugger group were; 36.3 +/- 0.6, 35.6 +/- 1.0, 36.5 +/- 0.6, and 36.4 +/- 0.5 degrees C, respectively. Despite differences in heating characteristics, both convective warming systems were effective in maintaining perioperative normothermia in patients undergoing major abdominal and orthopedic surgery. Therefore, choice of warming system is dependent on other factors such as ergonomics and cost.

Comparison of Parecoxib and Proparacetamol in Endoscopic Nasal Surgery Patients

PurposeThe aim of the study was to compare the efficacy of parecoxib for postoperative analgesia after endoscopic turbinate and sinus surgery with the prodrug of acetaminophen, proparacetamol.Materials and MethodsFifty American Society of Anesthesiology (ASA) physical status I-II patients, receiving functional endoscopic sinus surgery (FESS) and endoscopic turbinectomy, were investigated in a prospective, randomized, double-blind manner. After local infiltration with 1% mepivacaine, patients were randomly allocated to receive intravenous (IV) administration of either 40 mg of parecoxib (n = 25) or 2 g of proparacetamol (n = 25) 15 min before discontinuation of total IV anaesthesia with propofol and remifentanil. A blinded observer recorded the incidence and severity of pain at admission to the post anaesthesia care unit (PACU) at 10, 20, and 30 min after PACU admission, and every 1 h thereafter for the first 6 postoperative h.ResultsThe area under the curve of VAS (AUCVAS) calculated during the study period was 669 (28 - 1901) cm·min in the proparacetamol group and 635 (26 - 1413) cm·min in the parecoxib group (p = 0.34). Rescue morphine analgesia was required by 14 patients (56%) in the proparacetamol group and 12 patients (48%) in the parecoxib (p ≥ 0.05), while mean morphine consumption was 5 - 3.5 mg and 5 - 2.0 mg in the proparacetamol groups and parecoxib, respectively (p ≥ 0.05). No differences in the incidence of side effects were recorded between the 2 groups. Patient satisfaction was similarly high in both groups, and all patients were uneventfully discharged 24 h after surgery.ConclusionIn patients undergoing endoscopic nasal surgery, prior infiltration with local anaesthetics, parecoxib administered before discontinuing general anaesthetic, is not superior to proparacetamol in treating early postoperative pain.

A Comparison of Single-Dose Caudal Clonidine, Morphine, or Hydromorphone Combined with Ropivacaine in Pediatric Patients Undergoing Ureteral Reimplantation

Caudal blockade is a common technique for pediatric postoperative analgesia. While safe and effective, caudal opioids are associated with troublesome side effects. Caudal clonidine may offer significant analgesic benefits. We prospectively compared the analgesic, side effect, and rehabilitation profiles of caudal clonidine, hydromorphone, or morphine in a group of 60 pediatric patients undergoing ureteral reimplantation. Patients aged 6 mo to 6 yr were evenly and randomly enrolled in a double-blind manner. Patients received a single caudal dose of 2 mcg/kg of clonidine, 10 mcg/kg of hydromorphone, or 50 mcg/kg of morphine, combined with 1.0 mL/kg of 0.2% ropivacaine with epinephrine. After sevoflurane in oxygen/air anesthesia, all subjects received proxy nurse-controlled analgesia with morphine. Postoperative pain intensity, use of IV morphine, and side effects were assessed during the first 24 h. Oral intake and discharge home were recorded. Caudal clonidine resulted in less postoperative nausea and vomiting (P = 0.01) and pruritus (P = 0.007) than did caudal hydromorphone or caudal morphine. Caudal morphine produced more sustained initial analgesia than did caudal clonidine (P = 0.02). No difference was observed in pain scores, total morphine use, time to first oral intake or discharge home. No postoperative respiratory depression, excessive sedation, hypotension, or bradycardia was identified. Although caudal morphine may result in more sustained initial analgesia, caudal clonidine combined with nurse-controlled analgesia appears to provide comparable analgesia with fewer side effects. Based on these results, the use of caudal clonidine may be superior to caudal opioids after pediatric ureteral reimplantation.

Role of Magnesium Sulfate in Postoperative Pain Management for Patients Undergoing Thoracotomy

The purpose of this study was to investigate the effect of magnesium sulfate on pain management for post-thoracotomy patients. A prospective, randomized, controlled clinical study. University hospital. Twenty-four patients undergoing thoracotomy. After thoracotomy operations, patients were assigned to 2 groups. The control group received intravenous morphine (0.5 mg/h infusion, 0.3 mg patient-controlled anesthesia dose, 15-minute lockout time) via patient-controlled analgesia, and the magnesium group received magnesium sulfate (30-mg/kg bolus, 10 mg/kg/h infusion for 48 hours) plus the same patient-controlled analgesia protocol. Visual analog scale for pain score, sedation score, mean arterial pressure, heart rate, and valid and invalid analgesic demand were recorded. Serum magnesium levels were determined at postanesthesia care unit admission, at 24 hours, and at 48 hours. Side effects were also recorded. There were no significant differences between groups with respect to demographics, sedation score, and pain score. Cumulative mean morphine consumption was found to be higher in the control group compared with the magnesium group at 4, 8, and 48 hours (5.6 +/- 1 mg v 3.2 +/- 0.6 mg [p < 0.0001], 10.2 +/- 1.8 mg v 7.2 +/- 1.6 mg [p = 0.0003), and 40.2 +/- 4.5 mg v 34.8 +/- 6.3 mg [p = 0.02], respectively). Postoperative use of magnesium sulfate reduced opioid consumption for pain after thoracotomy operations.

Desflurane versus sevoflurane for laparoscopic gastroplasty in morbidly obese patients

Study Objective To determine if desflurane results in a faster emergence as measured by time to eye opening compared to sevoflurane in morbidly obese patients undergoing laparoscopic gastroplasty. Study Design Prospective, randomized, double-blinded study. Setting Tertiary care hospital. Patients 70 patients with a body mass index of 35 or higher undergoing laparoscopic gastroplasty. Interventions Patients were randomized into two groups to receive either desflurane or sevoflurane for maintenance of general anesthesia. Measurements Intraoperative measured variables included the time from when the inhalation agent was turned off (no agent delivered) to eye opening and the time from when the inhalation agent was turned off to extubation. Postanesthesia care unit (PACU)–measured variables on admission and at 15 minute intervals until discharge included oxygen saturation (Sp o 2), blood pressure, heart rate, pain and nausea Visual Analog Scale (VAS) scores, emesis, modified Aldrete score, and Mini-Mental Status (MMS) examination score. Main Results No differences were noted in demographic data, total surgical operative time, times from turning inhalation agent off to eye opening and extubation, or average length of stay in PACU. No differences were noted with respect to pain VAS, treatment for pain, modified Aldrete scores, emesis, or treatment for postoperative nausea or emesis. Differences were noted in PACU nausea VAS at 15 minutes, PACU nausea VAS at discharge, and PACU-MMS score at 45 minutes; however, multivariate analysis of variance revealed no differences between groups over the repeated PACU measured time periods in nausea VAS ( P = 0.17) or in MMS ( P = 0.34). Higher heart rates in the desflurane group were observed during PACU admission (82.3 ± 9.8 vs 74.4 ± 13.4 bpm, P < 0.01) and 15 minutes post PACU admission (79.4 ± 12.1 vs 71.3 ± 13.2 bpm, P = 0.01). Conclusions In morbidly obese patients undergoing laparoscopic gastroplasty, emergence, as measured by time to eye opening, did not differ between desflurane and sevoflurane, with similar recovery characteristics.

Omission of fentanyl during sevoflurane anesthesia decreases the incidences of postoperative nausea and vomiting and accelerates postanesthesia recovery in major breast cancer surgery

Our purpose was to investigate the effect of omission of fentanyl during sevoflurane anesthesia on the incidences of postoperative nausea and vomiting and on postanesthesia recovery in female patients undergoing major breast cancer surgery. Female patients (American Society of Anesthesiologists [ASA] physical status [PS] class I-II; age, 28-84 years) undergoing major breast cancer surgery were randomized to one of two anesthesia maintenance groups: sevoflurane-fentanyl anesthesia (SF; n = 25) or fentanyl-free sevoflurane anesthesia (S; n = 26). All patients were administered with propofol 2 mg x kg(-1) intravenously for anesthesia induction, a laryngeal mask airway was placed, and they received rectal diclofenac and local infiltration anesthesia. Anesthesia was maintained with sevoflurane in oxygen-air and they breathed spontaneously. The patients in group SF received fentanyl 0.1 mg intravenously and those in group S received normal saline during anesthesia. Group SF revealed higher incidences of postoperative nausea (68% vs 27%) and vomiting (32% vs 8%) in the first 24 postoperative hours than group S. The median (25th-75th percentile) length of time from postanesthesia care unit (PACU) admission to ambulation was significantly longer in group SF (n = 23) at 195 min (158-219 min), than in group S, at 141 min (101-175 min). Two patients in group SF could not walk during the PACU stay. Omission of fentanyl during sevoflurane anesthesia, combined with diclofenac and local infiltration anesthesia, decreases the incidences of postoperative nausea and vomiting and accelerates postanesthesia recovery in patients undergoing major breast cancer surgery.

Postoperative Results after Desflurane or Sevoflurane Combined with Remifentanil in Morbidly Obese Patients

This randomized prospective study with blinded postanesthesia care unit (PACU) observers compared the recovery profiles in morbidly obese patients who received sevoflurane or desflurane for maintenance of anesthesia in combination with a remifentanil target controlled infusion (TCI). 50 morbidly obese patients scheduled for laparoscopic gastric banding were included to receive BIS-guided sevoflurane or desflurane anesthesia with BIS-triggered inhalation boli in combination with remifentanil TCI. In the PACU, the following recovery scores were investigated: Modified Aldrete score, a modified Observers' Assessment of Alertness/Sedation Scale (OAA/S), pain numerical rating scale (NRS), oxygen saturation (SpO(2)) and postoperative nausea and vomiting (PONV). OAA/S and NRS pain scores showed a similar evolution in both groups from the moment of PACU admission up to 120 minutes after admission. In both groups, patients showed no serious hypoxemia during PACU stay. Incidence of PONV was shorter lasting in the sevoflurane group compared to the desflurane group. No clinically relevant difference was found in recovery in the PACU between morbidly obese patients anesthetized with desflurane or sevoflurane. Both agents resulted in satisfactory recovery in morbidly obese patients.

Preemptive Analgesia With Bupivacaine for Segmental Mastectomy

Preemptive analgesia is the concept of providing analgesia before surgical incision, resulting in less postoperative pain. The purpose of this study is to determine if preemptive and/or postoperative local anesthetic infiltration of bupivacaine in patients undergoing segmental mastectomy results in less postoperative pain compared with patients receiving placebo. In this prospective, double-blinded study, 120 patients were randomized into 4 groups: group 1, preincisional (10 mL) and postoperative (10 mL) wound infiltration of 0.5% bupivicaine, (+Pre+Post); group 2, preincisional bupivacaine (10 mL) and postoperative infiltration (10 mL) of placebo (normal saline solution), (+Pre-Post); group 3, preincisional placebo (10 mL) and postoperative bupivacaine (10 mL), (-Pre+Post); or group 4, preincisional (10 mL) and postoperative infiltration of placebo (10 mL), (-Pre-Post). All patients received a standardized laryngeal mask general anesthetic. Data were recorded at the following time intervals: preoperative admission, postanesthesia care unit (PACU) admission, PACU stay, stepdown-unit admission, stepdown-unit stay, hospital discharge, and 24 hours post operation. No difference was noted with respect to preoperative pain visual analog scale (VAS, 0-100 mm), surgical duration, PACU stay time, stepdown-unit stay time, incidence of postoperative nausea, or treatment for nausea in all measured time periods. The placebo group (group 4) had significantly higher mean pain VAS scores during the early postoperative period (PACU admission and PACU stay) compared to the other groups (PACU admission: group 1 = 2 +/- 8, group 2 = 4 +/- 11, group 3 = 3 +/- 15, group 4 = 17 +/- 21, P < .01; PACU stay: group 1 = 6 +/- 13, group 2 = 6 +/- 10, group 3 = 10 +/- 21, group 4 = 20 +/- 18, P < .01). Likewise, the number of patients who reported pain (pain frequency) was significantly higher in group 4 (placebo) compared with all other groups at PACU admission, PACU stay, stepdown-unit admission, and stepdown-unit stay (P < or = .01). Preincisional and/or postoperative wound bupivacaine infiltration lacks preemptive analgesic effects for segmental mastectomy.

Impact of surgical sequencing on post anesthesia care unit staffing

This paper analyzes the impact of sequencing rules on the phase I post anesthesia care unit (PACU) staffing and over-utilized operating room (OR) time resulting from delays in PACU admission. The sequencing rules are applied to each surgeon's list of cases independently. Discrete event simulation shows the importance of having a sufficient number of PACU nurses. Sequencing rules have a large impact on the maximum number of patients receiving care in the PACU (i.e., peak of activity). Seven sequencing rules are tested, over a wide range of scenarios. The largest effect of sequencing was on the percentage of days with at least one delay in PACU admission. The best rules are those that smooth the flow of patients entering in the PACU (HIHD (Half Increase in OR time and Half Decrease in OR time) and MIX (MIX OR time)). We advise against using the LCF (Longest Cases First) and equivalent sequencing methods. They generate more over-utilized OR time, require more PACU nurses during the workday, and result in more days with at least one delay in PACU admission.

Does dexmedetomidine prevent emergence delirium in children after sevoflurane‐based general anesthesia?

Emergence agitation or delirium (ED) is a frequent phenomenon in children recovering from general anesthesia (GA). Dexmedetomidine, an alpha2 receptor agonist, has analgesic and sedative properties that might be helpful in the management of ED. We studied the effects of a continuous perioperative infusion of 0.2 microg.kg(-1).h(-1) dexmedetomidine on the incidence of ED in 50 children aged 1-10 years scheduled for sevoflurane-based GA. Following inhalation induction of GA, the children were randomly assigned into dexmedetomidine or placebo Groups D and S, respectively. The infusion of 0.2 microg.kg(-1).h(-1) dexmedetomidine or equal volume of saline was started after securing the airway. Depth of anesthesia was maintained by adjusting the concentration of sevoflurane to achieve a Bispectral Index Score of 40-60. Intraoperative hemodynamics were recorded every 5 min and the trachea was extubated at the end of the procedure. Perioperative pain management was determined by the blinded anesthesia team, and the study drug infusion was maintained for 15 min following the postanesthesia care unit (PACU) admission. ED and pain scores were evaluated by a blinded observer. The incidence of ED was statistically significantly different between the two groups, 26% in Group D Vs 60.8% in Group S (P = 0.036). Additionally, the number of episodes of ED was lower in Group D (P < 0.017). Pain scores and the times to extubate and discharge from PACU were the same. The perioperative infusion of 0.2 microg.kg(-1).h(-1) dexmedetomidine decreases the incidence and frequency of ED in children after sevoflurane-based GA without prolonging the time to extubate or discharge.

Comparison of remifentanil and alfentanil during anaesthesia for patients undergoing direct laryngoscopy without intubation

Remifentanil and alfentanil are opioids often used during direct laryngoscopy (DL). This prospective, randomized study compared these agents with respect to haemodynamic and Bispectral Index (BIS) responses, glottic visualization, and rapidity of recovery (spontaneous ventilation, eye opening) in DL without intubation. A total of 60 patients undergoing DL were randomized into two groups: remifentanil (R) and alfentanil (A). Anaesthesia was induced with propofol 2.5 mg kg(-1) and the opioid was administered 1 min later (R=2 microg kg(-1) or A=30 microg kg(-1) over 30 s). DL was commenced 1 min after (corresponding to 3 min after the beginning of induction). Glottic visualization, opioid and/or propofol re-injection, spontaneous ventilation recovery, and eye opening were recorded. During DL, mean arterial pressure (MAP) increased by 6% in the R group vs 20% in the A group (P<0.05) when compared with post-induction values without affecting heart rate or BIS. No significant difference was observed between groups with respect to glottic exposure, opioid and/or propofol re-injection, and spontaneous ventilation recovery (mean (SEM) 3.8 (0.6) min, R group vs 3.2 (0.7) min, A group, NS) or eye opening (7.1 (1.1) min, R group vs 7.4 (0.9) min, A group, NS). Thirty minutes after postanaesthesia care unit (PACU) admission, MAP returned to its pre-induction value in the R group (104 (3) vs 109 (3) at baseline, NS), whereas in the A group MAP remained significantly lower at this time point (96 (4) vs 106 (3) at baseline, P<0.05). This study showed that only remifentanil prevented MAP increase without adverse effects such as bradycardia during DL, and prevented MAP decrease 30 min after PACU admission.

Hand-cleansing during postanesthesia care.

Transmission of microorganisms from the hands of healthcare workers is the main source of cross-infection and can be prevented by hand-cleansing. The authors assessed the compliance rate with hand-cleansing practices in the postanesthesia care unit and investigated factors associated with noncompliance. Patient care activities, indications for and compliance of postanesthesia care unit staff with hand-cleansing, defined as either washing hands with soap and water or rubbing hands with alcohol, were monitored at the time of patient admission and during their stay. Multivariate analysis identified predictors of noncompliance with hand-cleansing on admission after adjustment for confounders. A total of 3,143 patient care activities, including 1,091 opportunities for hand-cleansing at high or medium risk for cross-transmission, were recorded among 187 patients. The higher the workload, the higher the number of indications for hand-cleansing and the lower the compliance. Average compliance with hand-cleansing at postanesthesia care unit admission was 19.6%. Independent predictors for noncompliance included caring for patients older than 65 yr (odds ratio, 2.23; 95% confidence interval, 1.40-3.57) and those recovering from clean/clean-contaminated surgery (odds ratio, 2.27; 95% confidence interval, 1.11-4.76), as well as high intensity of patient care (odds ratio, 1.01 per patient care activity; 95% confidence interval, 1.0-1.02). Compliance with hand-cleansing for patients already admitted to the postanesthesia care unit was 12.5%. Failure to cleanse hands during patient care is common in the postanesthesia care unit and is associated with identifiable factors. The close relation between the intensity of patient care and noncompliance argues that hand-cleansing should not be viewed as a problematic individual behavior only, and system change must be considered in prevention strategies.

Propofol-ketamine versus propofol-fentanyl for outpatient laparoscopy : Comparison of postoperative nausea, emesis, analgesia, and recovery

Study objective To compare postoperative nausea, emesis, analgesia, and recovery between propofol-ketamine and propofol-fentanyl in outpatient laparoscopic tubal ligations with general anesthesia. Study design Prospective, randomized, blinded study. Setting Tertiary-care women’s hospital. Patients 120 ASA physical status I and II ambulatory patients scheduled for elective laparoscopic tubal ligation. Interventions Patients were randomized to two groups to receive either ketamine (1-1.5 mg/kg) or fentanyl (3-5 μg/kg). Measurements Measured variables included total dose of ketamine, fentanyl, propofol, and operating time. Vital signs, pain visual analog scale scores (VAS), nausea VAS, presence of emesis, treatment for nausea and vomiting, pruritus, sedation, and presence of dreaming were recorded on postanesthesia care unit (PACU) admission, PACU discharge, stepdown unit admission, and hospital discharge. Results are expressed as means ± SD or medians and analyzed using t -test, Chi-square, or Mann-Whitney (p < 0.05). Main results No differences were noted with respect to propofol dose, operating times, pain or nausea VAS scores, emesis, treatment for nausea and vomiting, pruritus, and sedation on PACU admission, PACU discharge, stepdown unit admission, and hospital discharge. The ketamine group had a higher heart rate, required more pain medication, and had a higher frequency of dreaming on PACU admission than the fentanyl group. These differences became insignificant on PACU discharge. Conclusions For outpatient laparoscopic tubal ligations with general anesthesia, propofol-ketamine does not improve postoperative nausea, emesis, analgesia or recovery compared with the propofol-fentanyl combination.

Influence of thiopental and propofol on postoperative cognitive recovery in the elderly patient undergoing general anesthesia

Study Objective: To assess mental and psychomotor recovery following induction of anesthesia with thiopental or propofol in elderly patients undergoing general anesthesia. Design: Randomized, prospective, double-blind study. Setting: Large referral hospital. Patients: 40 elderly patients ASA physical status I-III (>65 years) undergoing abdomino-pelvic surgery with an estimated surgical time of at least 90 minutes. Interventions: All patients received combined epidural-general anesthesia. After establishing a T 6 sensory blockade, patients were randomized to receive either thiopental or propofol for induction of general anesthesia. The induction drug was slowly titrated until loss of eyelash reflex was noted. Thereafter, all patients received desflurane (2% to 3% end-tidal) and 70% nitrous oxide (N 2O) in oxygen for maintenance of general anesthesia. To facilitate tracheal intubation, intravenous alfentanil 10 μg/kg and atracurium 0.4 mg/kg were administered. Perioperative analgesia was maintained with epidural bupivacaine. Measurements and Main Results: A digit substitution test (DSST) and shape-sorter test, as well as patient-generated 100-mm visual analog score (VAS; 0 = minimal and 100 = maximal) for anxiety, sleepiness, and coordination, were performed during the preanesthetic interview, on postanesthesia care unit admission, and at 15, 45, 90, and 120 minutes thereafter. To induce loss of consciousness, either thiopental 2.5 ± 1.0 mg/kg or propofol 1.6 ± 0.6 mg/kg was administered. The mean anesthetic time was 109 ± 30 minutes and 114 ± 38 minutes for the thiopental and propofol groups, respectively. Emergence, extubation, and orientation times, as well as time to follow commands, were unaffected by patient randomization. Similarly, the DSST and shape-sorter tests, in addition to the patient-generated VAS for pain, anxiety, and coordination, were similar among groups. However, irrespective of treatment modality, return to baseline digit substitution and shape-sorter scores were significantly delayed (p < 0.01). Conclusion: When compared to thiopental, propofol does not facilitate improved cognitive recovery in geriatric patients undergoing prolonged surgery.

Factors influencing stay in the postanesthesia care unit: a prospective analysis

Study Objective: To identify indicators of prolonged length of stay (LOS) in the postanesthesia care unit (PACU) and to test the following hypotheses: (1) that patient age, pain medication administration at the time of PACU admission, length of surgery, and cardiovascular, pulmonary, and pain responses postoperatively predict prolonged PACU LOS and (2) that cardiovascular and pulmonary symptoms preoperatively predict cardiovascular and pulmonary symptoms postoperatively. Design: Prospective, observational analysis. Setting: PACU of a university teaching hospital. Patients: 1,067 patients scheduled for surgery with general anesthesia between February and September 1996, 18 years of age or older. Measurement and Main Results: 11.2% of the variation in prolonged PACU LOS can be predicted by age, pain medication at the time of PACU admission, and postoperative cardiovascular, pulmonary, and pain symptoms. A significant number of patients who did not report a prior history experienced postoperative cardiovascular and pulmonary symptoms. Conclusion: Patient history and postoperative symptoms predict only a small percentage of prolonged PACU stays. Organizational factors may be a more important predictor of prolonged PACU stay. Additionally, assessment of cardiovascular and pulmonary history needs refinement to improve prediction of patient responses postoperatively.

The Successful Implementation of Pharmaceutical Practice Guidelines? Far From Convincing!

Department of Anesthesiology, Duke University Medical Center, Box 3094, Durham, North Carolina 27710.In Reply:-We appreciate the concerns that are raised by Drs. Bailey and Egan in their letter. However, their primary contention, that the extra 3 min per case that are spent between the operating room (OR) and the postanesthesia care unit (PACU) would negate all savings in drugs costs, is fallacious. Their misconception is a common one (repeated in Dr. Riley's letter), so it merits a more complete explanation here. Only a partial explanation (because of limitations on length) can be found in the text of our article. Although it is true that the OR is an expensive environment, it is an expensive environment for a variety of reasons, including administration, cleaning, nursing labor, equipment, and so on. The behavior of most OR costs [1] is such that no actual savings are generated from such a small (3 min) change in operational efficiency. A simplified explanation of the way that hospital accounting systems routinely calculate OR costs/min is necessary to understand this. First, all expenditures are summed and put in the numerator, and all minutes of operation become the denominator. Shaving 3 min from each case does not change any cost that goes into figuring the numerator. Labor costs are unlikely to change, even in institutions who pay their nurses by the hour rather than by the shift. The 3 min added per case in our study, at most (see below) would simply increase the number of minutes (the denominator) used by the hospital accounting system and serve to decrease the cost/min for running the OR. Actual dollars spent would not change. The accounting criticism that Drs. Bailey and Egan (and Dr. Riley, see next letter) offer is not valid in the real world of hard currency.Looking at this from another angle, if one were to approach any OR director and say, “I can cut three minutes off of each and every case if you simply hand me 1 million dollars,” not a single OR manager in the United States would make that deal. That is because no real savings in dollars accrue to the institution; all that happens is the cost/min of running the OR would increase slightly to account for the fact that the same costs are spread out over fewer minutes of operation.Further, we did not measure the actual turnover time between cases during this period. It is entirely conceivable that the extra couple of minutes that were required were not wasted by the OR nurses as they broke down their trays, and therefore no extension of operating room time occurred.The same reasoning used in assessing the “costs” of a few added minutes applies to the extra PACU admission. The extra 45 min/day of work, at a random interval, in exchange for 1 million dollars/yr savings, would be considered a good bargain. Patients recovering from MAC anesthesia, if they do need recovery room care, do not usually require the same close supervision as someone recovering from a long general anesthetic. The actual cost to the institution is negligible.There are always physicians who respond strongly to any discussion of practice guidelines. Their concerns may be legitimate, or they may simply reflect a fear of doing things differently from what has been done in the past and which are viewed as “tried and true.” In this case, Drs. Bailey and Egan suggest the superiority of certain narcotics. If it really made a difference what narcotic one chose, we would all choose the best one. We all have our patients' best interests at heart. The fortunate news (or unfortunate news if one is in the narcotic research business) is that it is not what drugs one administers but how one administers them that really makes a difference. We would welcome further outcome studies that would document the advantages of the more expensive drugs in a clinical setting. The differences between drugs seen in randomized, controlled studies cannot always be realized in the complex arena of perioperative patient flow.We are well aware of the limitations of our study, although our conclusions are valid. The cost savings are real. The institution is better because of the efforts we have made. And our patients are just as safe.David A. Lubarsky, M.D.Department of Anesthesiology; Duke University Medical Center; Box 3094; Durham, North Carolina 27710(Accepted for publication July 29, 1997.)

Dissection of the Posterior Pharynx Resulting in Acute Airway Obstruction

Dissection of the Posterior Pharynx Resulting in Acute Airway Obstruction

Hyperthermia Requiring Prolonged Administration of High-Dose Dantrolene in the Postoperative Period

Hyperthermia Requiring Prolonged Administration of High-Dose Dantrolene in the Postoperative Period