Acute pain management in the postanesthesia care unit

The Analgesic Properties of a Music Intervention in the Postanesthesia Care Unit

PURPOSE

The purpose of this study was to determine whether a combined music pharmacological intervention was an effective multimodal approach to reduce adult pain in the postanesthesia care unit (PACU).

DESIGN

A prospective, randomized control trial study.

METHODS

Participants were recruited in the preoperative holding area on the day of surgery by the principal investigators. Music was selected by the patient following the informed consent process. Participants were randomized either to the intervention group or the control group. Patients in the intervention group received music in addition to standard pharmacological protocol while the control group received only the standard pharmacological protocol. Measured outcomes were change in visual analog pain scores and length of stay.

FINDINGS

In this cohort (N = 134), 68 participants (50.7%) received the intervention, and 66 participants (49.3%) were in the control group. Paired t tests showed that pain scores for the control group worsened by an average of 1.45-points (95% CI: 0.75, 2.15; P < .001) compared to 0.34-points in the intervention group and was not significant (P = .314) as scores went from 1 out of 10 to 1.4 out of 10. Both control and intervention groups experienced pain, with the control group's overall pain scores worsening over time. This finding was statistically significant (P = .023). No statistically significant difference was noted in the average PACU length of stay (LOS).

CONCLUSIONS

The addition of music to the standard postoperative pain protocol demonstrated a lower average pain score on discharge from the PACU. The absence of a difference in LOS may be due to the confounding variables (eg, general versus spinal anesthesia or a difference in voiding time).

The Outcomes of an Opioid-Free Anaesthetic Plan in Fourteen Dogs Undergoing Enucleation Using an Ultrasound-Guided Supra-Temporal Retrobulbar Block: A Retrospective Case Series

The objective of this retrospective case series is to report the outcomes of an opioid-free anesthetic plan in dogs undergoing enucleation surgery. A total of 14 dogs were admitted for enucleation between March and December 2020. A multimodal approach to perioperative analgesia was used, with a focus on retrobulbar anesthesia. A combination of an ultrasound-guided retrobulbblock with a supratemporal approach in association with ketamine, dexmedetomidine and non-steroidal anti-inflammatory drugs was used in the reported cases. Intraoperative nociception was defined as an increase of 20% from the baseline in one or more of the following parameters: heart rate, respiratory rate or mean arterial pressure. An ultrasound-guided retrobulbar block in an opioid-free anesthesia regime was effective at managing the perioperative analgesia of 13 out of 14 dogs. In only one case, a bolus of fentanyl was administered to treat intraoperative nociception. Recovery was uneventful in all the dogs, and the postoperative pain scores remained below the intervention threshold at all time points. To the authors' knowledge, this is the first reported case series of opioid-free anesthesia for enucleation in dogs.

Assessment of patients' satisfaction with the postanesthesia care unit service at University Hospital in Al Khobar, KSA

Objectives

The quality of health care is individually and subjectively reflected through patients' level of satisfaction, as well as the optimality and effectiveness of the provided postoperative pain management. The provision of postanesthesia care unit (PACU) service in hospitals has led to overall positive outcomes, in addition to the enhancement of patients' satisfaction with the provided pain management service. This study assessed patients' level of satisfaction with PACU service at a university hospital and discussed different factors that might have contributed to the level of satisfaction.

Methods

A prospective cross-sectional study was carried out among patients after being discharged from PACU. The study took place at King Fahad Hospital of the University in Al Khobar, KSA between November 2021 and February 2022. The data were collected using a three-section predesigned questionnaire.

Results

Two hundred patients were included in this study. Nearly all patients (95.5%) were satisfied with the provided pain management service. Almost all patients (99.5%) indicated that the PACU staff was courteous and professional during the entire pain management service. More patients complained about pain before using analgesia and this difference was statistically significant (Z = 8.642; p < 0.001). The satisfaction rate was significantly higher in the older age group (>45 years) (Z = 2.114; p = 0.035), in patients with American Society of Anesthesiology (ASA) 3 physical status (H = 13.130; p = 0.001), and those with a previous surgical history (Z = 2.139; p = 0.032).

Conclusion

This study concluded that the level of patients' satisfaction with PACU service was high, and established a statistically significant association with age, ASA score, and previous surgical history. Healthcare providers should consider patient education and effective communication to increase patients' satisfaction level and improve the overall quality of care.

ABO blood group is not a predictive factor for the amount of early opioid consumption in postanesthesia care unit: a prospective cohort study in 3,316 patients

Background

Immediate postoperative pain in the postanesthesia care unit (PACU) is common. Titration of opioid is the most popular strategy for controlling early postoperative pain. ABO blood group has been found to be associated with pain perception. We aimed to find the factors including ABO blood group for predicting the amount of opioid requirement in PACU.

Methods

This prospective cohort study was performed in 3316 patients who underwent various kinds of anesthetic techniques and received immediate postoperative care in PACU. Preoperative, intraoperative and PACU data were collected. A directed acyclic graph (DAG) representing the hypothesized causal pathways of preoperative, intraoperative and PACU data were compiled prior to conducting multinomial logistic regression analysis. Statistical significance in all models was defined as a P-value < 0.05.

Results

Female sex, body mass index, preoperative use of gabapentin, preoperative anxiety score, anesthetic techniques, type of operation, amount of consumed intraoperative opioids, intraoperative use of paracetamol, parecoxib and ondansetron, duration of anesthesia and surgery, amount of blood loss, pain upon PACU arrival, use of paracetamol and parecoxib in PACU were found to be factors influencing amount of opioid consumption in PACU. ABO blood group was not associated with early postoperative opioid requirement.

Conclusions

A significant number of factors are related to amount of opioid requirement in PACU. Some factors can be adjusted to provide better pain relief in early postoperative period. However, ABO blood group is not identified to be a predictive factor for early postoperative opioid consumption in PACU.

The problem of postoperative respiratory depression

WHAT IS KNOWN AND OBJECTIVE

Postsurgical recovery is influenced by multiple pre-, intra- and perioperative pharmacotherapeutic interventions, including the administration of medications that can induce respiratory depression postoperatively. We present a succinct overview of the topic, including the nature and magnitude of the problem, contributing factors, current limited options, and potential novel therapeutic approach.

COMMENT

Pre-, intra- and perioperative medications are commonly administered for anxiety, anaesthesia, muscle relaxation and pain relief among other reasons. Several of the medications alone or in joint-action can be additive or synergistic producing respiratory depression. Given the large number of surgical procedures that are performed each year, even a small percentage of postoperative respiratory complications translates into a large number of affected patients.

WHAT IS NEW AND CONCLUSION

Due to the large number of surgeries performed each year, and the variety of medications used before, during, and after surgery, the occurrence of postoperative respiratory depression is surprisingly common. It is a significant medical problem and burden on hospital resources. There is a need for new strategies to prevent and treat the acute and collateral problems associated with postoperative respiratory depression.

Risk Factors for Moderate to Severe Pain during the First 24 Hours after Laparoscopic Bariatric Surgery While Receiving Intravenous Patient-Controlled Analgesia

Objective

To investigate the incidence of and risk factors for moderate to severe pain during the first 24 hours after laparoscopic bariatric surgery.

Materials and Methods

This retrospective study included morbidly obese patients who underwent laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass at a single institution between June 2016 and July 2018. Demographic, clinical, operative, and postoperative pain data from the postanesthesia care unit (PACU) and ward were analyzed. Intravenous patient-controlled analgesia (IV-PCA) was commenced before PACU discharge.

Results

Ninety-seven patients were included. The mean age was 38.60 ± 12.27 years, and the mean BMI was 45.04 ± 8.42 kg/m², and 69% were female. The incidence of moderate to severe pain was 75%. Moderate to severe pain during the first 24 hours was associated with young age, female sex, postoperative administration of NSAIDs, first pain score greater than 3 on arrival at the PACU, and inadequate pain control at PACU discharge. A multivariate analysis revealed that inadequate pain control at PACU discharge was the only factor independently associated with moderate to severe pain during the first 24 hours postoperatively (p=0.011). From PACU discharge to the end of postoperative day 3, moderate to severe pain at the end of each 24-hour period was a significant predictor of moderate to severe pain in the subsequent 24-hour period (p=0.011, p < 0.001, and p=0.004, respectively).

Conclusions

Moderate to severe pain was experienced by 75% of patients undergoing laparoscopic bariatric surgery and receiving IV-PCA after PACU discharge. Inadequate pain control at PACU discharge was the only independent risk factor for moderate to severe pain during the first 24 hours postoperatively.

Intravenous Acetaminophen Improves Outcomes After Transapical Transcatheter Aortic Valve Replacement

OBJECTIVE

Complications with opioid-based postoperative pain management have led to guideline recommendations for a multimodal analgesia strategy incorporating nonopioid agents. We evaluated the opioid-sparing effect of intravenous acetaminophen in patients undergoing transapical transcatheter aortic valve replacement.

METHODS

A multimodal pain management strategy that incorporated intravenous acetaminophen was retrospectively evaluated in 43 patients undergoing transapical transcatheter aortic valve replacement between November 2012 and March 2014. Before intravenous acetaminophen formulary availability, 23 patients received standard postoperative pain management interventions including intravenous narcotics and oral narcotics/acetaminophen. After intravenous acetaminophen availability, 20 patients received intravenous acetaminophen (4 g/d, ≥4 doses) and supplemental intravenous and nonacetaminophen oral narcotics. Daily narcotic dose (standardized to morphine equivalents), drug cost, and hospital length of stay were compared between groups.

RESULTS

Baseline characteristics were similar between intravenous acetaminophen (n = 20) and nonintravenous acetaminophen (n = 23) patients including the Society of Thoracic Surgery mortality risk (10.5% vs 9.0%, P = 0.3). The median number of intravenous acetaminophen doses was 6.5 (interquartile range = 4.0-18.5), with a median cost per patient of US $221 (interquartile range = $136-$629). Patients who received intravenous acetaminophen used significantly fewer morphine equivalents on postoperative day 0 compared with patients not receiving intravenous acetaminophen (22.5 vs 45.0 morphine equivalents, P = 0.03) and had a shorter median length of stay (5.0 vs 7.0 days, P = 0.007). After adjusting for the Society of Thoracic Surgery risk, intravenous acetaminophen continued to be associated with a reduction in median postoperative length of stay [-1.9 days (95% confidence interval = -0.9 to -8.2 days), P = 0.049].

CONCLUSIONS

In patients undergoing transapical transcatheter aortic valve replacement, a multimodal pain management strategy incorporating intravenous acetaminophen was associated with reductions in narcotic use on the day of surgery and overall length of stay.

Trauma Trainees' Multiple Competing Goals in Opioid Prescription Communication

Prescription opioids and heroin account for more than half of all drug overdose fatalities, costing an estimated 115 American lives every day. The ongoing opioid epidemic devastates communities and represents a tremendous burden to the national economy and health care system. In 2016, the Centers for Disease Control and Prevention and the White House Office of National Drug Control Policy proposed action to train prescribers on the proper dispensing of opioids, which are indispensable pharmacologic resources for treating acute pain resulting from a traumatic injury or surgery. Trauma surgeons who prescribe opioids for severe pain embark on patient consultations with multiple and conflicting goals respective to their roles as a healers of the suffering, regulators of illicit substances, members of a greater medical system working to contain an opioid epidemic, and moral beings with a distinct set of preferences, experiences, social norms, and practice philosophies. Semistructured interviews with 17 trauma and surgical residents and fellows at a southeastern academic medical center in the United States generated descriptive data regarding prescribing practices and patient communication. Guided by the multiple goals framework, the current research presents three prominent themes depicting the problematic convergence of identity, task, and relational goals during opioid-prescribing conversations between trauma trainees and their patients.

Non-invasive patient-controlled analgesia in the management of acute postoperative pain in the hospital setting

OBJECTIVE

Acute postoperative pain is experienced by the majority of hospitalized patients undergoing surgical procedures, with many reporting inadequate pain relief and/or high levels of dissatisfaction with their pain management. Patient-controlled analgesia (PCA) ensures patient involvement in acute pain control, a key component for implementing a quality management system. This narrative article overviews the clinical evidence for conventional PCA and briefly discusses new, non-invasive PCA systems, namely the sufentanil sublingual tablet system (SSTS) and the fentanyl iontophoretic transdermal system (FITS).

METHODS

A Medline literature search ("patient-controlled analgesia" and "acute postoperative pain") was conducted to 1 April 2017; results from the main clinical trials are discussed. Additional literature was identified from the reference lists of cited publications.

RESULTS

Moderate to low quality evidence supports opioid-based intravenous PCA as an efficacious alternative to non-patient-controlled systemic analgesia for postoperative pain. However, despite the benefits of PCA, conventional intravenous PCA is limited by system-, drug- and human-related issues. The non-invasive SSTS and FITS have demonstrated good efficacy and safety in placebo- and intravenous morphine PCA-controlled trials, and are associated with high patient/healthcare practitioner satisfaction/ease of care ratings and offer early patient mobilization.

CONCLUSIONS

Evidence-based guidelines for acute postoperative pain management support the use of multimodal regimens in many situations. As effective and safe alternatives to conventional PCA, and with the added benefits of being non-invasive, easy to use and allowing early patient mobilization, the newer PCA systems may complement multimodal approaches, or potentially replace certain regimens, in hospitalized patients with acute postoperative pain.

Bilateral thoracic Paravertebral block for immediate postoperative pain relief in the PACU: a prospective, observational study

Background

To investigate the feasibility, effectiveness and safety of bilateral thoracic paravertebral block (TPVB) in the post anesthesia care unit (PACU) for pain relief in participants after laparotomy.

Methods

A single shot of bilateral TPVB with 25 ml of 0.2% ropivacaine and 5 mg dexamethasone in combination for both sides at the 8th thoracic transverse level (T8) was performed on 201 participants who complained moderate to severe pain on arrival to PACU after laparotomy. The visual analog scale (VAS) pain scores at rest and on cough, heart rate, blood pressure, and pulse oximetry before and after bilateral TPVB for up to 1 h were recorded. The VAS Pain scores at rest and on cough at 24 h after bilateral TPVB were also recorded.

Results

Bilateral TPVB was carried out successfully in all participants. The VAS pain scores at rest and on cough were 7.9 ± 1.6 and 8.7 ± 1.3 respectively pre-bilateral TPVB. The VAS pain scores at rest and on cough were significantly decreased to 1.1 ± 1.2 and 2.1 ± 1.6 respectively (P < 0.001) at 60 min after bilateral TPVB and to 2.1 ± 1.7 and 3.8 ± 1.9 at rest and on cough respectively ((P < 0.001) at 24 h after bilateral TPVB. At 10 min post-bilateral TPVB, only systolic blood pressure was reduced from 122 ± 19 mmHg to 111 ± 18 mmHg (P = 0.007) but then gradually became stable. No complications related to bilateral TPVB were observed.

Conclusion

Bilateral TPVB can be provided for pain relief to the participants who suffer from moderate to severe pain after upper laparotomy in the PACU.

Trial registration

Chinese Clinical Trial Registry: ChiCTR-ONN-16009229, Registered on 10 September 2016.

Prevalence and characterization of postoperative pain in the Postanaesthesia Care Unit

INTRODUCTION

Immediate postoperative pain occurs initially after surgery, while the patient is in the Post-Anaesthesia Recovery Unit. Very few studies assess this pain in this most immediate phase.

OBJECTIVE

Cross-sectional study of the prevalence and characteristics of immediate postoperative pain in patients after surgery.

MATERIAL AND METHODS

Between August 2014 and February 2015, a sample of 503 patients from the Post-Anaesthesia Recovery Unit was followed. Immediate postoperative pain was assessed (by the patient and the researcher) using the visual analogue scale (VAS; range 0-10) on 5 occasions after surgery. The impact of numerous factors (age, gender, type of surgery, type of anaesthesia and analgesic) on the pain, as well as variation in vital signs and the presence of side effects, were analysed.

RESULTS

Assessment of the pain showed overall VAS values of 2.2±2.8 on all occasions. Pain was reported to be of greatest intensity 20min after the patients' arrival in the Post-Anaesthesia Recovery Unit (P<.001). The VAS values reported by the researcher (1.4±2.0) were lower than those reported by the patients. Although there was a very strong correlation (R²=0.82; P<.001) and they followed a parallel distribution, there was moderate concordance (kappa=0.4). Plastic surgery and neurosurgery were the specialties with the highest percentages of VAS values in the strong intensity range (8-10). Patients with regional block techniques (with or without general anaesthesia) had lower VAS values than other general anaesthesia groups. Male patients and older patients displayed less pain than female and young patients, respectively (P<.001).

CONCLUSIONS

Studying the characteristics of postoperative pain at such an early stage allows for improved management. It helps to predict, according to the type of surgery and the anaesthesia used, those patients in which higher VAS values may be seen and to better adapt analgesic therapy.

A comparative study of the effect of clonidine, fentanyl, and the combination of both as adjuvant to intrathecal bupivacaine for postoperative analgesia in total abdominal hysterectomy

Background and Aims:

The aim of this study was to evaluate the level of sensory block, onset and duration of motor block, postoperative analgesia, and adverse effects of combination of clonidine and fentanyl given intrathecally with hyperbaric bupivacaine (HB).

Material and Methods:

Three hundred and twenty eight patients were randomized into four groups. Group bupivacaine (group B) received 15 mg of HB; group bupivacaine clonidine (group BC) received 15 mg of HB plus 25 μg clonidine; group bupivacaine fentanyl (group BF) received 15 mg of HB plus 25 μg fentanyl and group bupivacaine clonidine fentanyl (group BCF) received 15 mg of HB plus 25 μg clonidine and 25 μg fentanyl intrathecally. All groups were evaluated for level of sensory block, onset and duration of motor block, postoperative analgesia, VAS score, sedation score and adverse effects of study drugs. All the data were analyzed using unpaired t-test. P < 0.05 was considered significant.

Results:

The level of sensory block, onset, and duration of motor block were comparable in all groups. Total duration of analgesia was 407.3 ± 20 min in group BCF compared to 242.1 ± 2 min and 209.2 ± 16 in groups BC and BF, respectively. Lesser doses of rescue analgesic were required in group BCF. The time interval from intrathecal injection to two-segment regression was statistically significant in study groups. Only 2.4% patients showed mild sedation in BCF group.

Conclusion:

We found that combination of intrathecal clonidine and fentanyl along with bupivacaine increases the total duration of analgesia without significant side effects.

Estimating the Effect of Intravenous Acetaminophen for Postoperative Pain Management on Length of Stay and Inpatient Hospital Costs

Introduction

The provision of safe, effective, cost-efficient perioperative inpatient acute pain management is an important concern among clinicians and administrators within healthcare institutions. Overreliance on opioid monotherapy in this setting continues to present health risks for patients and increase healthcare costs resulting from preventable adverse events. The goal of this study was to model length of stay (LOS), potential opioid-related complications, and costs for patients reducing opioid use and adding intravenous acetaminophen (IV APAP) for management of postoperative pain.

Methods

Data for this study were de-identified inpatient encounters from The Advisory Board Company across 297 hospitals from 2012–2014, containing 2,238,433 encounters (IV APAP used in 12.1%). Encounters for adults ≥18 years of age admitted for cardiovascular, colorectal, general, obstetrics and gynecology, orthopedics, or spine surgery were included. The effects of reducing opioids and adding IV APAP were estimated using hierarchical statistical models. Costs were estimated by multiplying modeled reductions in LOS or complication rates by observed average volumes for medium-sized facilities, and by average cost per day or per complication (LOS: US$2383/day; complications: derived from observed charges).

Results

Across all surgery types, LOS showed an average reduction of 18.5% (10.7–32.0%) for the modeled scenario of reducing opioids by one level (high to medium, medium to low, or low to none) and adding IV APAP, with an associated total LOS-related cost savings of $4.5 M. Modeled opioid-related complication rates showed similar improvements, averaging a reduction of 28.7% (5.4–44.0%) with associated cost savings of $0.2 M. In aggregate, costs decreased by an estimated $4.7 M for a medium-sized hospital. The study design demonstrates associations only and cannot establish causal relationships. The cost impact of LOS is modeled based on observed data.

Conclusions

This investigation indicates that reducing opioid use and including IV APAP for postoperative pain management has the potential to decrease LOS, opioid-related complication rates, and costs from a hospital perspective.

Funding

Mallinckrodt Pharmaceuticals.

Current Approaches in Hip and Knee Arthroplasty Anaesthesia

Risk assesment, preoperative drug regulation, the anesthesia and analgesia techniques are very important and the effectivity on success of surgery is great. So, these topics in arthroplasty were reviewed under current knowledge.

Comparing parecoxib and ketorolac as preemptive analgesia in patients undergoing posterior lumbar spinal fusion: a prospective randomized double-blinded placebo-controlled trial

Background

Poor postoperative pain control is frequently associated with complications and delayed discharge from a hospital. Preemptive analgesia is one of the methods suggested for reducing postoperative pain. Opioids are effective for pain control, but there known addictive properties make physicians cautious about using them. Parecoxib and ketorolac are potent non-opioid NSAIDs that are attractive alternative drugs to opioids to avoid opioid-related side effects. However, there are no good head-to-head comparisons between these two drugs in the aspect of preemptive analgesic effects in lumbar spinal fusion surgery. This study aimed to compare the efficacy in terms of postoperative pain control and safety of parecoxib with ketorolac as preemptive analgesia in posterior lumbar spinal fusion patients.

Methods

A prospective, double-blinded randomized controlled trial was carried out in patients undergoing posterior lumbar spinal fusion, who were randomized into 3 groups (n = 32). Parecoxib, ketorolac or a placebo was given to each patient via injection around 30 minutes prior to incision. The efficacy of postoperative pain control was assessed by a verbal numerical rating score (0–10). And various postoperative things were monitored for analysis, such as total opioid consumption, complications, and estimated blood loss.

Results

Both the ketorolac and parecoxib groups showed significantly better early postoperative pain reduction at the postanesthesia care unit (PACU) than the control group (p < 0.05). There were no differences between the pain scores of ketorolac and parecoxib at any time points. Complications and bleeding were not significantly different between all three groups.

Conclusions

Preemptive analgesia using both ketorolac and parecoxib showed a significantly better early postoperative pain control in the PACU than the control group in patients undergoing lumbar spinal fusion.

Trial registration

ClinicalTrials.gov NCT01859585. Registered 15 May 2013.

Impact of intraoperative acetaminophen administration on postoperative opioid consumption in patients undergoing hip or knee replacement

BACKGROUND

Opioid utilization for acute pain has been associated with numerous adverse events, potentially resulting in longer inpatient stays and increased costs.

OBJECTIVE

To examine the effect of intravenous (IV) acetaminophen administered intraoperatively on postoperative opioid consumption in adult subjects who underwent hip or knee replacement.

METHODS

This retrospective cohort study evaluated postoperative opioid consumption in 176 randomly selected adult subjects who underwent hip or knee replacement at Duke University Hospital (DUH). Eighty-eight subjects received a single, intraoperative, 1 g dose of IV acetaminophen. The other subjects did not receive any IV acetaminophen. This study evaluated mean opioid consumption (in oral morphine equivalents) during the 24-hour postoperative period in the 2 groups. Other endpoints included length of stay in the postanesthesia care unit (PACU), incidence of oversedation, need for acute opioid reversal, and adjunctive analgesic utilization.

RESULTS

Subjects who were given a single dose of intraoperative acetaminophen received an average of 149.3 mg of oral morphine equivalents during the 24 hours following surgery compared to 147.2 mg in participants who were not exposed to IV acetaminophen (P = .904). The difference in average length of PACU stay between the IV acetaminophen group (163 minutes) and those subjects not exposed to IV acetaminophen (169 minutes) was not statistically significant (P = .588). No subjects in the study experienced oversedation or required acute opioid reversal.

CONCLUSION

There was not a statistically significant difference in postoperative opioid consumption between patients receiving and not receiving IV acetaminophen intraoperatively.

The length of stay in the post-anaesthesia care unit correlates with pain intensity, nausea and vomiting on arrival

Background

The benefit of the post-anaesthesia care unit (PACU) with respect to an early detection of postoperative complications is beyond dispute. From a patient perspective, prevention and optimal management of pain, nausea and vomiting (PONV) are also of utmost importance. The aims of the study were therefore to prospectively measure pain and PONV on arrival to the PACU and before discharge and to determine the relationship of pain and PONV to the length of stay in the PACU.

Methods

Postoperative pain was assessed over 30 months using a numeric rating scale on admittance to the PACU and before discharge; in addition, PONV was recorded. Statistical analysis was done considering gender, age, American Society of Anesthesiologists (ASA) classification, surgical speciality, anaesthesia technique, duration of anaesthesia, intensity of nursing and length of stay.

Results

Data of 12,179 patients were available for analysis. The average length of stay in the PACU was 5.7 ± 5.9 h, whereas regular PACU patients stayed for 3.2 ± 1.9 h and more complex IMC patients stayed for 15.1 ± 6.0 h. On admittance, 27% of patients were in pain and the number decreased to 13% before discharge; 3% experienced PONV. Risk factors for increased pain determined by multivariate analysis were female gender; higher ASA classification; general, cardiac and orthopaedic surgery and prolonged case duration. In more complex IMC patients, pain scores were higher on arrival but dropped to similar levels before discharge compared to regular PACU patients. Female gender and postoperative pain were risk factors for postoperative vomiting. Pain and PONV on arrival correlated with length of stay in the PACU. Pain- or PONV-free patients stayed almost half of the time in the PACU compared to patients with severe pain or vomiting on arrival.

Conclusions

The majority of PACU patients had good pain control, both on admittance and before discharge, and the overall incidence of PONV was low. Managing patients in the PACU could achieve a significant reduction of pain and PONV. The level of pain and presence of PONV on admittance to the PACU correlate with and act as predictors for increased length of PACU stay.

Inhibiting spinal neuron-astrocytic activation correlates with synergistic analgesia of dexmedetomidine and ropivacaine

Background

This study aims to identify that intrathecal (i.t.) injection of dexmedetomidine (Dex) and ropivacaine (Ropi) induces synergistic analgesia on chronic inflammatory pain and is accompanied with corresponding “neuron-astrocytic” alterations.

Methods

Male, adult Sprague-Dawley rats were randomly divided into sham, control and i.t. medication groups. The analgesia profiles of i.t. Dex, Ropi, and their combination detected by Hargreaves heat test were investigated on the subcutaneous (s.c.) injection of complete Freund adjuvant (CFA) induced chronic pain in rat and their synergistic analgesia was confirmed by using isobolographic analysis. During consecutive daily administration, pain behavior was daily recorded, and immunohistochemical staining was applied to investigate the number of Fos-immunoreactive (Fos-ir) neurons on hour 2 and day 1, 3 and 7, and the expression of glial fibrillary acidic protein (GFAP) within the spinal dorsal horn (SDH) on day 1, 3, 5 and 7 after s.c. injection of CFA, respectively, and then Western blot to examine spinal GFAP and β-actin levels on day 3 and 7.

Results

i.t. Dex or Ropi displayed a short-term analgesia in a dose-dependent manner, and consecutive daily administrations of their combination showed synergistic analgesia and remarkably down-regulated neuronal and astrocytic activations indicated by decreases in the number of Fos-ir neurons and the GFAP expression within the SDH, respectively.

Conclusion

i.t. co-delivery of Dex and Ropi shows synergistic analgesia on the chronic inflammatory pain, in which spinal “neuron-astrocytic activation” mechanism may play an important role.