Development and assessment of novel machine learning models to predict the probability of postoperative nausea and vomiting for patient-controlled analgesia.

Postoperative nausea and vomiting (PONV) can lead to various postoperative complications. The risk assessment model of PONV is helpful in guiding treatment and reducing the incidence of PONV, whereas the published models of PONV do not have a high accuracy rate. This study aimed to collect data from patients in Sichuan Provincial People's Hospital to develop models for predicting PONV based on machine learning algorithms, and to evaluate the predictive performance of the models using the area under the receiver characteristic curve (AUC), accuracy, precision, recall rate, F1 value and area under the precision-recall curve (AUPRC). The AUC (0.947) of our best machine learning model was significantly higher than that of the past models. The best of these models was used for external validation on patients from Chengdu First People's Hospital, and the AUC was 0.821. The contributions of variables were also interpreted using SHapley Additive ExPlanation (SHAP). A history of motion sickness and/or PONV, sex, weight, history of surgery, infusion volume, intraoperative urine volume, age, BMI, height, and PCA_3.0 were the top ten most important variables for the model. The machine learning models of PONV provided a good preoperative prediction of PONV for intravenous patient-controlled analgesia.

The cost-effectiveness analysis of analgesic treatment options for postoperative pain following laparotomy surgeries.

BACKGROUND: Postoperative pain control remains unsatisfactory. Patients who underwent laparotomy may have moderate to severe acute postoperative pain. Comparative cost-effectiveness of the following postoperative pain treatment options remains to be investigated: patient-controlled intravenous analgesia (PCIA) with flurbiprofen therapy, flurbiprofen monotherapy, parecoxib monotherapy, or dezocine monotherapy. AIM: To provide a cost-effectiveness analysis (CEA) of four analgesic regimens for patients with postoperative pain following laparotomy surgeries. METHOD: Patients with postoperative pain following laparotomy were retrospectively reviewed from a postoperative pain management database created by pharmacists, and divided into four groups according to analgesic regimens. The clinical outcomes were visual analogue scale (VAS) scores and the incidence of adverse drug events. The CEA was conducted by developing a decision tree model based on retrospective data. The maximum incremental cost-effectiveness ratio (ICER) of the four regimens was used as the willingness-to-pay (WTP) value. Meanwhile, the uncertainty of the base-case results was examined by one-way and probabilistic sensitivity analyses. RESULTS: A total of 677 patients were included in the retrospective study. PCIA with flurbiprofen therapy had the lowest VAS scores at 6, 24, 48 h postoperatively. Based on the base-case results, PCIA plus flurbiprofen was the optimal regimen with the highest effectiveness, while flurbiprofen monotherapy had the lowest cost. PCIA plus flurbiprofen was the optimal regimen even with a WTP value of 0 dollars. CONCLUSION: PCIA plus flurbiprofen therapy was the optimal regimen. Parecoxib monotherapy was more cost-effective than flurbiprofen monotherapy. The findings may guide the selection of postoperative pain management.

A survey of labour epidural practices at obstetric anesthesia fellowship programs in the United States.

PURPOSE: Labour epidural analgesia (LEA) is an evolving field. Various neuraxial techniques and dosing regimens are available to the modern obstetric anesthesia provider, allowing for significant practice variability. To begin a search for consensus on optimal care, we sought to query fellowship training practices for LEA. METHODS: We conducted an electronic survey of institutions with American Council for Graduate Medical Education-accredited obstetric anesthesiology fellowship programs. We studied the frequency of epidural initiation techniques, including combined spinal epidural (CSE), dural puncture epidural, and epidural bolus. For maintenance techniques, we appraised the use of continuous epidural infusion, programmed intermittent bolus (PIEB), and patient-controlled epidural analgesia (PCEA). RESULTS: Of 40 institutions surveyed, we received 32 responses (80% response rate). Twenty-eight of 40 (70%) were included in the analysis. A plurality of institutions (12/28; 43%) preferred CSE, and among those who used CSE, 23/27 (85%) included intrathecal opioids. A majority of institutions used protocols with PIEB (55%), while almost all (92%) used PCEA. Most participants (88%) reported using dilute concentration maintenance infusions of 0.1% bupivacaine/ropivacaine or less. CONCLUSION: Despite significant variability in LEA practice, some clear patterns emerged in our survey, including preference for opioid-containing CSE and maintenance with PIEB, PCEA, and dilute epidural solutions.

RéSUMé: OBJECTIF: L'analgésie péridurale obstétricale (APO) est un domaine en évolution. Diverses techniques neuraxiales et posologies sont disponibles pour le praticien en anesthésie obstétricale moderne, ce qui permet une variabilité significative de la pratique. Pour démarrer une recherche de consensus sur les soins optimaux, nous avons cherché à déterminer les pratiques d'APO dans le cadre de formation des fellows. MéTHODE: Nous avons réalisé une enquête électronique auprès d'établissements possédant des programmes de fellowship en anesthésiologie obstétricale accrédités par l'American Council for Graduate Medical Education. Nous avons étudié la fréquence des techniques de péridurale, notamment de rachi-péridurale combinée (RPC), de péridurale avec ponction durale et de bolus péridural. Pour les techniques de maintien, nous avons évalué l'utilisation de l'analgésie péridurale par perfusion continue, l'administration programmée de bolus périduraux (PIEB; programmed intermittent epidural bolus) et l'analgésie péridurale contrôlée par la patiente (APCP). RéSULTATS: Sur les 40 établissements sondés, nous avons reçu 32 réponses (taux de réponse de 80 %). Vingt-huit des 40 (70 %) établissements ont été inclus dans l'analyse. Plusieurs institutions (12/28; 43 %) ont répondu qu'elles préféraient la RPC, et parmi celles qui utilisaient la RPC, 23/27 (85 %) incluaient des opioïdes intrathécaux. La majorité des établissements utilisaient des protocoles avec le PIEB (55 %), tandis que presque tous (92 %) utilisaient l'APCP. La plupart des établissements participants (88 %) ont rapporté utiliser des perfusions de maintien à des concentrations diluées de bupivacaïne/ropivacaïne de 0,1 % ou moins. CONCLUSION: Malgré une variabilité significative dans la pratique de l'APO, certaines tendances claires ont émergé dans notre sondage, notamment une préférence pour les RPC contenant des opioïdes et le maintien avec un PIEB, une APCP et des solutions péridurales diluées.

[Critical incidents in acute pain management-A risk analysis of CIRS reports]. / Kritische Ereignisse in der Akutschmerztherapie ­ eine Risikoanalyse von CIRS-Meldungen.

BACKGROUND: Areas of activity with many intersections pose an increased risk for errors and critical incidents. Therefore, procedures for acute pain therapy are potentially associated with an increased risk for adverse patient outcomes. OBJECTIVE: The aim was to identify and grade the risk of critical incidents in the context of acute pain management. MATERIAL AND METHODS: The register of the nationwide reporting system critical incident reporting system of the Professional Association of German Anesthesiologists, the German Society for Anesthesiology and Intensive Care Medicine and the Medical Center for Quality in Medicine (CIRSmedical Anesthesiology) was screened for incidents concerning pain management. Out of 5365 cases reported nationwide up to 24 March 2020, 508 reports with the selection criterion "pain" could be identified and reviewed and 281 reports (55%) were included in a systematic analysis. RESULTS: Of the 281 reports most came from anesthesiology departments (94%; 3% from surgery departments and 3% from other departments). The reported cases occurred most frequently on normal wards but a relevant proportion of the reports concerned intermediate and intensive care units or areas covered by a pain service (PS). Based on the description of the incident in the report, an involvement of the PS could be assumed for 42% of the cases. In terms of time, most of the events could be assigned to normal working hours (90%) and working days (84%; weekends 16%). The analyzed reports related to parenteral administration of analgesics (40%) and central (40%) or peripheral regional anesthesia procedures (23%) and 13% of the reports related to patient-controlled intravenous analgesia (PCIA; multiple answers possible). Most of the events were caused by technical errors, communication deficits and deviations from routine protocols. A relevant number of the cases were based on mix-ups in the administration route, the dosage, or the active agent. About one third of the sources of error were of an organizational nature, 59% of the cases posed a possible vital risk and in 16% of cases patients had vital complications. The risk grading by risk matrix resulted in an extremely high risk in 7%, a high risk in 62%, a moderate risk in 25% and a low risk in 6% of the cases. Comparing risk assessment of events with involvement of different analgesic methods, multiple medication, combination of analgesic methods or involvement of PS showed no significant differences. Likewise, no differences could be identified between the risk assessments of events at different superordinate cause levels. If more than one overriding cause of error had an impact, initially no higher risk profile was found. CONCLUSION: Incidents in the context of acute pain management can pose high risks for patients. Incidents or near-incidents are mostly related to mistakes and lack of skills of the staff, often due to time pressure and workload as well as to inadequate organization.

Patient controlled analgesia for the management of acute pain in the emergency department: A systematic review.

BACKGROUND: The most common presenting complaint to the emergency department (ED) is pain. Several studies have shown that a large proportion of ED patients either receive no or sub-optimal analgesia. Patient-controlled analgesia (PCA) pumps used in the post-operative setting has shown to decrease total opioid consumption and has increased patient and nurse satisfaction. OBJECTIVE: The purpose of this systematic review was to evaluate clinical trials that have used PCAs in the ED setting, to evaluate safety and efficacy as well as patient and healthcare provider experience. METHODS: A search of PubMed, MEDLINE, and the Cochrane Database was conducted using the MESH search terms emergency department, patient-controlled analgesia, and acute pain up to September 2021. These terms were searched in all fields of publication and were limited to the English-language articles, clinical "human" studies, and studies that included the use of patient-controlled analgesia in the setting of the emergency department. RESULTS: The search initially identified 227 potentially relevant articles and a total of 10 studies met criteria for inclusion. ED use of PCA therapy was associated with increased patient satisfaction, decreased pain scores, and an overall increase in opioid consumption. CONCLUSION: The quality, the differences in study methods and outcome measures used, and heterogeneity of the studies performed to date do not provide adequate evidence to support its widespread use in the ED. Well-designed studies conducted in the ED are still needed to evaluate the ideal patient population to whom these PCAs may provide the most benefit as well as a robust cost-analysis to ensure feasibility of use in the future.

A retrospective audit of pain assessment and management post-caesarean section at New Somerset Hospital in Cape Town, South Africa.

BACKGROUND: The most common major surgical procedure performed worldwide is the caesarean section (CS). Effective pain management is a priority for women undergoing this procedure, to reduce the incidence of persistent pain (a risk factor for postpartum depression), as well as optimise maternal-neonatal bonding and the successful establishment of breastfeeding. Multimodal analgesia is the gold standard for post-CS analgesia. At present, no perioperative pain management protocols could be identified for the management of patients presenting for CS at regional hospitals in South Africa. This audit aimed to review the folders of patients who underwent CS, with particular reference to perioperative pain management guidelines for CS. METHODS: A descriptive, retrospective, cross-sectional audit was conducted. Three hundred folders (10% of the annual number of caesarean procedures performed) from New Somerset Hospital, a regional hospital in Cape Town, South Africa were reviewed. RESULTS: The women were a mean age of 30 years (standard deviation [s.d.]: 6.2). Median gravidity was 3 (interquartile range [IQR]: 2-3) and parity was 1 (IQR: 1-2); 52% had previously undergone a CS. In 93.3% cases, spinal anaesthesia was employed for CS. Pain assessment was poor, with only 55 (18%) patients having their pain assessed on the day of the operation. Analgesia was prescribed in over 98% of the patients, however, medication was only administered as prescribed in 32.6%. Non-steroidal anti-inflammatory drugs (NSAIDs) were prescribed in 5% of cases. None of the patients received a patient-controlled analgesia (PCA), transversus abdominis plane (TAP) block, or wound infusion catheter as supplementary strategies. CONCLUSION: Pain management for post-CS patient at this hospital is lacking. There is the need for the implementation of a structured assessment tool to improve administration of analgesics in these patients. In addition, the reasons for the omission of NSAIDs from the analgesia regimen requires investigation. Hospital requires post-CS pain protocols to guide management especially in resource-limited settings.

A preliminary assessment of vital-signs-integrated patient-assisted intravenous opioid analgesia (VPIA) for postsurgical pain.

BACKGROUND: We developed a Vital-signs-integrated Patient-assisted Intravenous opioid Analgesia (VPIA) analgesic infusion pump, a closed-loop vital signs monitoring and drug delivery system which embodied in a novel algorithm that took into account patients' vital signs (oxygen saturation, heart rate). The system aimed to allow responsive titration of personalized pain relief to optimize pain relief and reduce the risk of respiratory depression. Moreover, the system would be important to enable continuous monitoring of patients during delivery of opioid analgesia. METHODS: Nineteen patients who underwent elective gynecological surgery with postoperative patient controlled analgesia (PCA) with morphine were recruited. The subjects were followed up from their admission to the recovery room/ ward for at least 24 h until assessment of patient satisfaction on the VPIA analgesic infusion pump. RESULTS: The primary outcome measure of incidence of oxygen desaturation showed all patients had at least one episode of oxygen desaturation (< 95%) during the study period. Only 6 (31.6%) patients had oxygen desaturation that persisted for more than 5 min. The median percentage time spent during treatment that oxygen saturation fell below 95% was 1.9%. Fourteen (73.7%) out of 19 patients encountered safety pause, due to transient oxygen desaturation or bradycardia. The patients' median [IQR] pain scores at rest and at movement after post-op 24 h were 0.0 [2.0] and 3.0 [2.0], respectively. The average morphine consumption in the first 24 h was 12.5 ± 7.1 mg. All patients were satisfied with their experience with the VPIA analgesic infusion pump. CONCLUSIONS: The use of VPIA analgesic infusion pump, when integrated with continuous vital signs monitor and variable lockout algorithm, was able to provide pain relief with good patient satisfaction. TRIAL REGISTRATION: This study was registered on clinicaltrials.gov registry (NCT02804022) on 28 Feb 2016.

Application of preoperative assessment of pain induced by venous cannulation in predicting postoperative pain in patients under laparoscopic nephrectomy: a prospective observational study.

BACKGROUND: Postoperative pain is the most prominent concern among surgical patients. It has previously been reported that venous cannulation-induced pain (VCP) can be used to predict postoperative pain after laparoscopic cholecystectomy within 90 mins in the recovery room. Its potential in predicting postoperative pain in patients with patient-controlled intravenous analgesia (PCIA) is worth establishing. The purpose of this prospective observational study was to investigate the application of VCP in predicting postoperative pain in patients with PCIA during the first 24 h after laparoscopic nephrectomy. METHODS: One hundred twenty patients scheduled for laparoscopic nephrectomy were included in this study. A superficial vein on the back of the hand was cannulated with a standard-size peripheral venous catheter (1.1 × 3.2 mm) by a nurse in the preoperative areas. Then the nurse recorded the VAS score associated with this procedure estimated by patients, and dichotomized the patients into low response group (VAS scores < 2.0) or high response group (VAS scores ≥2.0). After general anesthesia and surgery, all the patients received the patient-controlled intravenous analgesia (PCIA) with sufentanil. The VAS scores at rest and on coughing at 2 h, 4 h, 8 h, 12 h, 24 h, the effective number of presses and the number of needed rescue analgesia within 24 h after surgery were recorded. RESULTS: Peripheral venous cannulation-induced pain score was significantly correlated with postoperative pain intensity at rest (rs = 0.64) and during coughing (rs = 0.65), effective times of pressing (rs = 0.59), additional consumption of sufentanil (rs = 0.58). Patients with venous cannulation-induced pain intensity ≥2.0 VAS units reported higher levels of postoperative pain intensity at rest (P < 0.0005) and during coughing (P < 0.0005), needed more effective times of pressing (P < 0.0005) and additional consumption of sufentanil (P < 0.0005), and also needed more rescue analgesia (P = 0.01) during the first 24 h. The odds of risk for moderate or severe postoperative pain (OR 3.5, 95% CI 1.3-9.3) was significantly higher in patients with venous cannulation-induced pain intensity ≥2.0 VAS units compared to those <2.0 VAS units. CONCLUSIONS: Preoperative assessment of pain induced by venous cannulation can be used to predict postoperative pain intensity in patients with PCIA during the first 24 h after laparoscopic nephrectomy. TRIAL REGISTRATION: We registered this study in a Chinese Clinical Trial Registry (ChiCTR) center on July 6 2019 and received the registration number: ChiCTR1900024352.

A micro-costing study: comparing a standard intravenous patient-controlled analgesia system with a novel sublingual patient-controlled analgesia system.

BACKGROUND: Judicious spending in healthcare is of paramount importance, particularly when introducing new devices or interventions. These products or interventions need to be economically efficient both directly and indirectly. An accepted method of cost estimation is micro-costing. Micro-costing involves direct enumeration and costing of every input consumed in the treatment of a particular patient when using new device, medicine or intervention. In our study, we investigated the cost of using a novel sublingual (SL) patient-controlled analgesia (PCA) device and compared it with our conventional intravenous (IV) PCA device. METHODS: A previous study performed in our institution produced a cost per use of IV PCA device at €97. This compared with a previous European study published in this journal in 2010 which showed a similar figure of €96 per use of IV PCA device. In our comparative study, we used a case record form (CRF) to incorporate a cost to all consumables used, staff time and equipment used to both the SL PCA and the IV PCA. RESULTS: A total of 60 patients of similar demographic were included in our study. The cost of an IV PCA episode was €97.89 and €182.32 for an SL PCA episode. Standl et al. (2010) showed that the average cost of an IV PCA episode was €96.40 with 78% of this being made up of staff time. SL PCA was more efficacious in certain patient groups and in certain surgical groups. CONCLUSION: After performance of a micro-costing study, the less costly IV PCA episode was statistically significant compared with a SL PCA episode. However, the associated staff costs were less with a SL PCA episode. We performed a micro-costing study on a novel sublingual PCA device and compared it with a conventional intravenous PCA device. All resources were included and compared.

Patient-Controlled Intravenous Morphine Analgesia Combined with Transcranial Direct Current Stimulation for Post-Thoracotomy Pain: A Cost-Effectiveness Study and A Feasibility For Its Future Implementation.

This prospective randomized study aims to evaluate the feasibility and cost-effectiveness of combining transcranial direct current stimulation (tDCS) with patient controlled intravenous morphine analgesia (PCA-IV) as part of multimodal analgesia after thoracotomy. Patients assigned to the active treatment group (a-tDCS, n = 27) received tDCS over the left primary motor cortex for five days, whereas patients assigned to the control group (sham-tDCS, n = 28) received sham tDCS stimulations. All patients received postoperative PCA-IV morphine. For cost-effectiveness analysis we used data about total amount of PCA-IV morphine and maximum visual analog pain scale with cough (VASP-Cmax). Direct costs of hospitalization were assumed as equal for both groups. Cost-effectiveness analysis was performed with the incremental cost-effectiveness ratio (ICER), expressed as the incremental cost (RSD or US$) per incremental gain in mm of VASP-Cmax reduction. Calculated ICER was 510.87 RSD per VASP-Cmax 1 mm reduction. Conversion on USA market (USA data 1.325 US$ for 1 mg of morphine) revealed ICER of 189.08 US$ or 18960.39 RSD/1 VASP-Cmax 1 mm reduction. Cost-effectiveness expressed through ICER showed significant reduction of PCA-IV morphine costs in the tDCS group. Further investigation of tDCS benefits with regards to reduction of postoperative pain treatment costs should also include the long-term benefits of reduced morphine use.

Effects of thoracic epidural anesthesia/analgesia on the stress response, pain relief, hospital stay, and treatment costs of patients with esophageal carcinoma undergoing thoracic surgery: A single-center, randomized controlled trial.

BACKGROUND: Appropriate postoperative pain management can improve outcomes in patients with esophageal cancer (EC). OBJECTIVE: To compare different combinations of anesthesia and analgesia techniques in patients with EC undergoing open thoracotomy. METHODS: This randomized, controlled, open-label trial enrolled 100 patients with EC (aged 40-65 years; American Society of Anesthesiologists [ASA] grade I/II) receiving elective surgery at Jiangsu Province Hospital (China) between July 2016 and December 2017. Patients were randomized to 4 groups (n = 25 per group): total intravenous general anesthesia plus patient-controlled intravenous analgesia (TIVA/PCIA); TIVA plus patient-controlled epidural analgesia (TIVA/PCEA); thoracic epidural anesthesia with intravenous general anesthesia plus PCIA (TEA-IVA/PCIA); and TEA-IVA/PCEA (TEA-IVA plus PCEA). Primary outcomes were plasma cortisol level (measured at baseline, 2 h after skin incision, surgery completion, and 24 and 48 h post-surgery) and pain (assessed at 24, 48, and 72 hours post-surgery using a visual analog scale). Secondary outcomes included time to first flatus, hospital stay and treatment costs. Postoperative adverse events (AEs) were analyzed. RESULTS: Baseline and operative characteristics were similar between the 4 groups. Plasma cortisol level increased (P <.05 vs baseline) earlier in the TIVA groups (2 h after skin incision) than in the TEA-IVA groups (24 h after surgery). At 48 hours after surgery, plasma cortisol had returned to baseline levels in the PCEA groups but not in the PCIA groups. VAS pain scores at rest and during coughing were lower in the PCEA groups than in the PCIA groups (P <.05). Compared with the PCIA groups, the PCEA groups had shorter time to first flatus and shorter hospital stay, while use of TEA-IVA lowered the costs of intraoperative anesthesia (P <.05). However, the PCEA groups had a higher incidence of nausea, vomiting, and pruritus. CONCLUSION: Thoracic epidural anesthesia/analgesia can reduce the stress response, improve postoperative recovery and reduce hospital stay and costs for patients with EC.

Is robotic hepatectomy cost-effective? In view of patient-reported outcomes.

BACKGROUND: Robotic hepatectomy has been accepted as an alternative for patients needing surgery. However, few reports addressed the patient-reported outcomes and long-term quality of life (QoL) of patients having undergone robotic liver surgery. METHODS: This study presented the QoL and cost-effectiveness associated with robotic and open hepatectomy by performing a comparative survey using two standardized questionnaires (Short Form-36 and Gastrointestinal Quality of Life Index). RESULTS: One hundred patients completed the study. The robotic group tended to experienced longer operation time but shorter length of hospital stay compared to open group. Moreover, the robotic group had faster return to daily activities, less need of patient-controlled anesthesia, and less wound-related complaints in long-term follow-up. The robotic group incurred higher peri-operative expenses; however, the cost of inpatient care was lower. CONCLUSIONS: Our study suggested that robotic hepatectomy provided good post-operative QoL and recovery of daily activity. However, efforts for lowering the financial burden of medical care by reducing the cost of robotic surgery is necessary for further application.

An assessment of early functional rehabilitation and hospital discharge in conventional versus robotic-arm assisted unicompartmental knee arthroplasty: a prospective cohort study.

AIMS: The objectives of this study were to compare postoperative pain, analgesia requirements, inpatient functional rehabilitation, time to hospital discharge, and complications in patients undergoing conventional jig-based unicompartmental knee arthroplasty (UKA) versus robotic-arm assisted UKA. PATIENTS AND METHODS: This prospective cohort study included 146 patients with symptomatic medial compartment knee osteoarthritis undergoing primary UKA performed by a single surgeon. This included 73 consecutive patients undergoing conventional jig-based mobile bearing UKA, followed by 73 consecutive patients receiving robotic-arm assisted fixed bearing UKA. All surgical procedures were performed using the standard medial parapatellar approach for UKA, and all patients underwent the same postoperative rehabilitation programme. Postoperative pain scores on the numerical rating scale and opiate analgesia consumption were recorded until discharge. Time to attainment of predefined functional rehabilitation outcomes, hospital discharge, and postoperative complications were recorded by independent observers. RESULTS: Robotic-arm assisted UKA was associated with reduced postoperative pain (p < 0.001), decreased opiate analgesia requirements (p < 0.001), shorter time to straight leg raise (p < 0.001), decreased number of physiotherapy sessions (p < 0.001), and increased maximum knee flexion at discharge (p < 0.001) compared with conventional jig-based UKA. Mean time to hospital discharge was reduced in robotic UKA compared with conventional UKA (42.5 hours (sd 5.9) vs 71.1 hours (sd 14.6), respectively; p < 0.001). There was no difference in postoperative complications between the two groups within 90 days' follow-up. CONCLUSION: Robotic-arm assisted UKA was associated with decreased postoperative pain, reduced opiate analgesia requirements, improved early functional rehabilitation, and shorter time to hospital discharge compared with conventional jig-based UKA.

The role of intraperitoneal ropivacaine in laparoscopic appendicectomy: a prospective, double-blinded randomized control Australian study.

BACKGROUND: Currently, intraoperative use of local anaesthetic is not routinely given in all laparoscopic appendicectomies. Although its use has been widely studied in laparoscopic hernia repairs, gynaecological laparoscopy and laparoscopic cholecystectomies, there are no published trials of the use of intraperitoneal local anaesthetic during laparoscopic appendicectomy in the Australasian setting. The aim of this study was to determine whether the use of intraperitoneal ropivacaine during laparoscopic appendicectomy will reduce the amount of post-operative opiate analgesia used, abdominal pain, post-operative nausea or vomiting, shoulder tip pain and length of hospital stay. METHODS: A randomized double-blinded placebo versus control trial was conducted with patients with clinically diagnosed appendicitis undergoing laparoscopic appendicectomy. Primary outcomes measured were the number of times the patient-controlled analgesia (PCA) button was pressed post-operatively and the average and total amount of fentanyl from PCA consumed during the post-operative period from 0 to 6 h and from 6 to 16 h. RESULTS: A total of 86 patients with 43 patients in the placebo normal saline group and 43 patients in the treatment ropivacaine group were included in the study. During the immediate post-operative period (0-6 h), there was a statistically significant reduction in the number of times the PCA button was pressed in the ropivacaine group compared to the normal saline group (16 versus 24 times, P = 0.02). CONCLUSION: Intraperitoneal ropivacaine has an analgesic effect for patients up to 6 h following emergency laparoscopic appendicectomy.

Effect of cultural background and healthcare environment on postoperative opioid requirement.

PURPOSE: The objective of this prospective observational study was to investigate the interactions between cultural background, healthcare environment, and postoperative pain experience. METHODS: We enrolled 128 Chinese patients living in rural mainland China and 134 patients in Hong Kong with a higher level of Western cultural influences (defined by educational attainment, place of residence, and ability to understand English). All patients had major abdominal surgery and received patient-controlled analgesia with intravenous morphine for postoperative pain relief. The primary endpoint was total opioid requirement up to 48 hr after surgery. Other measures included pain intensity, opioid-related side effects, and genetic markers for opioid responsiveness. RESULTS: The mean (95% confidence interval) cumulative opioid requirement, expressed as morphine equivalent, during the first 48 hr after surgery was significantly less in patients from mainland China (18.8 [15.7 to 22] mg) compared with patients from Hong Kong (42.0 [38.3 to 45.6] mg, P < 0.0001). In a multivariable analysis, opioid requirement was influenced by ethnicity, duration of surgery, and severity of pain upon admission to the postanesthetic care unit. CONCLUSIONS: These results suggest that postoperative pain behaviours and opioid requirement may be influenced by cultural background and healthcare environment in two populations of Chinese descent. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN12614000601639); registered 6 May, 2014.

RéSUMé: OBJECTIF: L'objectif de cette étude observationnelle prospective était d'étudier les interactions entre le contexte culturel, l'environnement de soins de santé et l'expérience de la douleur postopératoire. MéTHODES: Nous avons recruté 128 patients chinois vivant en zones rurales en Chine continentale et 134 patients vivant à Hong-Kong avec un haut niveau d'influences culturelles occidentales (définies par le niveau d'éducation atteint, le lieu de résidence et la capacité à comprendre l'anglais). Tous les patients avaient subi une chirurgie abdominale majeure et reçu une analgésie contrôlée par le patient par morphine intraveineuse pour le soulagement de la douleur postopératoire. Le critère d'évaluation principal était la demande totale en opioïdes pendant les 48 premières heures suivant la chirurgie. D'autres mesures ont inclus l'intensité de la douleur, les effets indésirables liés aux opioïdes et des marqueurs génétiques de sensibilité aux opioïdes. RéSULTATS: Le besoin cumulé moyen (intervalle de confiance à 95 %) cumulé en opioïdes, exprimé sous forme d'équivalent-morphine, au cours des 48 premières heures suivant la chirurgie était significativement inférieur pour les patients de Chine continentale (18,8 [15,7 à 22] mg) comparativement aux patients de Hong-Kong (42,0 [38,3 à 45,6] mg, P < 0,0001). Une analyse multifactorielle a montré que la demande en opioïdes était influencée par l'origine ethnique, la durée de l'intervention chirurgicale et l'intensité de la douleur au moment de l'arrivée dans l'unité de soins postanesthésiques. CONCLUSIONS: Ces résultats suggèrent que les comportements postopératoires envers la douleur et le besoin d'opioïdes peuvent être influencés par l'arrière-plan culturel et l'environnement des soins de santé dans deux populations différentes d'origine chinoise. ENREGISTREMENT DE L'ESSAI CLINIQUE: Registre des essais cliniques d'Australie et de Nouvelle-Zélande (ACTRN12614000601639); enregistré le 6 mai 2014.

The cost-effectiveness of epidural, patient-controlled intravenous opioid analgesia, or transversus abdominis plane infiltration with liposomal bupivacaine for postoperative pain management.

STUDY OBJECTIVE: Intravenous patient-controlled opioid analgesia (IVPCA), epidural analgesia and transversus abdominis plane (TAP) infiltrations are frequently used postoperative pain management modalities. The aim of this study was to conduct a cost-effectiveness analysis comparing the use of epidural, IVPCA, and TAP infiltrations with liposomal bupivacaine for analgesia in the first 72 h postoperatively in patients undergoing major lower abdominal surgery. DESIGN: Retrospective cost effectiveness analysis. SETTING: Operating room. PATIENTS: We obtained data on major lower-abdominal surgeries performed under general anesthesia on adult patients between January 2012 and July 2014. INTERVENTIONS: A cost-effectiveness analysis was comparing the use of epidural, IVPCA, and TAP infiltrations with liposomal bupivacaine for analgesia in the first 72 h postoperatively. MEASUREMENTS: A decision analytic model was used to estimate the health outcomes for patients undergoing major lower abdominal surgery. The primary outcome was time-weighted pain from 0 to 72 h after surgery, as measured by numerical rating scale pain scores. The analysis was conducted from the perspective of the hospital as the party responsible for most costs related to surgery. MAIN RESULTS: From the base case analysis, IVPCA was the optimal strategy regarding cost and effect. TAP with LB, however, was only narrowly dominated, while epidural was clearly dominated. From the sensitivity analysis at willingness-to-pay (WTP) of $150, IV PCA and TAP infiltration were each the optimal strategy for approximately 50% of the iterations. At WTP of $10,000, epidural was only the optimal strategy in 10% of the iterations. CONCLUSIONS: This is the first study in the literature to compare the cost-effectiveness of epidural, IVPCA, and TAP infiltrations with LB. Within reasonable WTP values, there is little differentiation in cost-effectiveness between IVPCA and TAP infiltration with LB. Epidural does not become a cost-effective strategy even at much higher WTP values.

[Continuous vs. intermitent intravenous analgesia for primary total knee replacement: analysis of the quality of the pain control, hospital stay and costs]. / Analgesia endovenosa continua versus analgesia endovenosa intermitente para reemplazo total de rodilla primario: análisis de la calidad analgésica, tiempo de hospitalización y costos económicos.

BACKGROUND: The International Association for the Study of Pain (IASP) defines pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Total knee arthroplasty is one of the orthopedic surgeries that manifests more pain in the first 24-48 hours, needing a multimodal analgesic therapy. The objective of this work is to compare two different intravenous analgesic modes applied to patients undergoing a primary total knee arthroplasty, analyzing the quality of pain control, hospital stay and costs. MATERIAL AND METHODS: Simple blind, comparative and prospective study comprised of 42 patients operated of total knee arthroplasty secondary to degenerative arthritis in the period between May 2016 and May 2017. RESULTS: The distribution of pain showed significant differences (p 0.0401) between both groups, indicating that the application of continuous pump for analgesia controls this symptom early. The hospital stay, on average, was different in the groups (p = 0.001), estimating about 15 hours less following the use of continuous pump. This strategy is globally more economic. DISCUSSION: The continuous infusion pump of analgesia compared with intermittent formal intravenous regimen showed better control of pain, decreasing the perception of pain by the patient, bettering the tolerance to physical therapy and reducing, on average, 15 hours of hospital stay, and thus, the final costs of the surgery.

INTRODUCCIÓN: La Asociación Internacional para el Estudio del Dolor (IASP, por sus siglas en inglés) define el dolor como una experiencia sensorial y emocional desagradable asociada a un daño tisular real o potencial. La artroplastía total de rodilla es una de las cirugías ortopédicas que cursa con más dolor en las primeras 24-48 horas, por lo que precisa de una terapia multimodal de analgesia. El objetivo de este trabajo es comparar dos modos analgésicos endovenosos diferentes aplicados a pacientes sometidos a cirugía de artroplastía total de rodilla primaria, analizando la calidad analgésica, el tiempo de hospitalización y los costos económicos. MATERIAL Y MÉTODOS: Estudio prospectivo, comparativo y simple ciego conformado por 42 pacientes intervenidos quirúrgicamente de artroplastía total de rodilla secundaria a artrosis degenerativa en el período comprendido entre Mayo de 2016 y Mayo de 2017. RESULTADOS: La distribución del dolor mostró diferencias significativas (p 0.0401) entre ambos grupos, indicando que la aplicación de analgesia mediante bomba continua controla este síntoma de manera temprana. El tiempo de hospitalización promedio fue diferente en los grupos (p = 0.001); se estimaron alrededor de 15 horas menos siguiendo el protocolo de bomba continua. Además, esta estrategia es globalmente más económica. CONCLUSIÓN: La bomba de infusión continua de analgesia compara da con la analgesia endovenosa reglada intermitente logró un mejor control del dolor, disminuyendo la percepción del mismo por parte del paciente, con una mejor tolerancia a la fisioterapia y reduciendo, en promedio, 15 horas de hospitalización y, por ende, los costos finales aproximados de la cirugía.

An economic analysis of patient controlled remifentanil and epidural analgesia as pain relief in labour (RAVEL trial); a randomised controlled trial.

OBJECTIVE: To compare the costs of a strategy of patient controlled remifentanil versus epidural analgesia for pain relief in labour. DESIGN: We performed a multicentre randomised controlled trial in 15 hospitals in the Netherlands, the RAVEL trial. Costs were analysed from a health care perspective alongside the RAVEL trial. POPULATION: Pregnant women of intermediate to high risk beyond 32 weeks gestation who planned vaginal delivery. METHODS: Women were randomised before the onset of labour, to receive either patient controlled remifentanil or epidural analgesia when pain relief was requested during labour. MAIN OUTCOME MEASURES: Primary outcome for effectiveness was satisfaction with pain relief, expressed as the area under the curve (AUC). A higher AUC represents higher satisfaction with pain relief. Here, we present an economic analysis from a health care perspective including costs from the start of labour to ten days postpartum. Health-care utilization was documented in the Case Report Forms and by administering an additional questionnaire. RESULTS: The costs in the patient controlled remifentanil group (n = 687) and in the epidural group (n = 671) were €2900 versus €3185 respectively (mean difference of -€282 (95% CI -€611 to €47)). The (non-significant) higher costs in the epidural analgesia group could be mainly attributed to higher costs of neonatal admission. CONCLUSION: From an economic perspective, there is no preferential pain treatment in labouring intermediate to high risk women. Since patient controlled remifentanil is not equivalent to epidural analgesia with respect to AUC for satisfaction with pain relief we recommend epidural analgesia as the method of choice. However, if appropriately counselled on effect and side effects there is, from an economic perspective, no reason to deny women patient controlled remifentanil.

Novel multimodal analgesia regimen improves post-TACE pain in patients with hepatocellular carcinoma.

BACKGROUD: Transarterial chemoembolization (TACE) is the primary palliative treatment for patients with unresectable hepatocellular carcinoma (HCC). However, it is often accompanied by postoperative pain which hinder patient recovery. This study was to examine whether preemptive parecoxib and sufentanil-based patient controlled analgesia (PCA) could improve the pain management in patients receiving TACE for inoperable HCC. METHODS: From June to December 2016, 84 HCC patients undergoing TACE procedure were enrolled. Because of the willingness of the individuals, it is difficult to randomize the patients to different groups. We matched the patients' age, gender and pain scores, and divided the patients into the multimodal group (n = 42) and control group (n = 42). Patients in the multimodal group received 40 mg of parecoxib, 30 min before TACE, followed by 48 h of sufentanil-based PCA. Patients in the control group received a routine analgesic regimen, i.e., 5 mg of dezocine during operation, and 100 mg of tramadol or equivalent intravenous opioid according to patient's complaints and pain intensity. Postoperative pain intensity, percentage of patients as per the pain category, adverse reaction, duration of hospital stay, cost-effectiveness, and patient's satisfaction were all taken into consideration when evaluated. RESULTS: Compared to the control group, the visual analogue scale scores for pain intensity was significantly lower at 2, 4, 6, and 12 h (all P < 0.05) in the multimodal group and a noticeably lower prevalence of post-operative nausea and vomiting in the multimodal group (31.0% vs. 59.5%). Patient's satisfaction in the multimodal group was also significantly higher than that in the control group (95.2% vs. 69.0%). No significant difference was observed in the duration of hospital stay between the two groups. CONCLUSION: Preemptive parecoxib and sufentanil-based multimodal analgesia regime is a safe, efficient and cost-effective regimen for postoperative pain control in HCC patients undergoing TACE.

Analgesia endovenosa continua versus analgesia endovenosa intermitente para reemplazo total de rodilla primario: análisis de la calidad analgésica, tiempo de hospitalización y costos económicos / Continuous versus intermittent intravenous analgesia for primary total knee replacement: analysis of the quality of the pain control, hospital stay and costs

Resumen: Introducción: La Asociación Internacional para el Estudio del Dolor (IASP, por sus siglas en inglés) define el dolor como una experiencia sensorial y emocional desagradable asociada a un daño tisular real o potencial. La artroplastía total de rodilla es una de las cirugías ortopédicas que cursa con más dolor en las primeras 24-48 horas, por lo que precisa de una terapia multimodal de analgesia. El objetivo de este trabajo es comparar dos modos analgésicos endovenosos diferentes aplicados a pacientes sometidos a cirugía de artroplastía total de rodilla primaria, analizando la calidad analgésica, el tiempo de hospitalización y los costos económicos. Material y métodos: Estudio prospectivo, comparativo y simple ciego conformado por 42 pacientes intervenidos quirúrgicamente de artroplastía total de rodilla secundaria a artrosis degenerativa en el período comprendido entre Mayo de 2016 y Mayo de 2017. Resultados: La distribución del dolor mostró diferencias significativas (p < 0.0401) entre ambos grupos, indicando que la aplicación de analgesia mediante bomba continua controla este síntoma de manera temprana. El tiempo de hospitalización promedio fue diferente en los grupos (p = 0.001); se estimaron alrededor de 15 horas menos siguiendo el protocolo de bomba continua. Además, esta estrategia es globalmente más económica. Conclusión: La bomba de infusión continua de analgesia comparada con la analgesia endovenosa reglada intermitente logró un mejor control del dolor, disminuyendo la percepción del mismo por parte del paciente, con una mejor tolerancia a la fisioterapia y reduciendo, en promedio, 15 horas de hospitalización y, por ende, los costos finales aproximados de la cirugía.

Abstract: Background: The International Association for the Study of Pain (IASP) defines pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Total knee arthroplasty is one of the orthopedic surgeries that manifests more pain in the first 24-48 hours, needing a multimodal analgesic therapy. The objective of this work is to compare two different intravenous analgesic modes applied to patients undergoing a primary total knee arthroplasty, analyzing the quality of pain control, hospital stay and costs. Material and methods: Simple blind, comparative and prospective study comprised of 42 patients operated of total knee arthroplasty secondary to degenerative arthritis in the period between May 2016 and May 2017. Results: The distribution of pain showed significant differences (p < 0.0401) between both groups, indicating that the application of continuous pump for analgesia controls this symptom early. The hospital stay, on average, was different in the groups (p = 0.001), estimating about 15 hours less following the use of continuous pump. This strategy is globally more economic. Discussion: The continuous infusion pump of analgesia compared with intermittent formal intravenous regimen showed better control of pain, decreasing the perception of pain by the patient, bettering the tolerance to physical therapy and reducing, on average, 15 hours of hospital stay, and thus, the final costs of the surgery.