Is outpatient continuous regional analgesia more effective and equally safe than single-shot peripheral nerve blocks after ambulatory orthopedic surgery?

INTRODUCTION: Continuous regional analgesia is an established technique for effective postoperative pain treatment, particularly after orthopedic surgical procedures. Even if it has been increasingly applied to the outpatient setting as well, many anesthesiologists are still reluctant to discharge patients with a perineural catheter in place. Aim of this review was to clarify the evidences about safety and effectiveness of outpatient continuous peripheral nerve blocks. EVIDENCE ACQUISITION: A systematic review of all prospective, randomized, double-blinded, placebo-controlled trials of the last 20 years on outpatient continuous peripheral nerve blocks after ambulatory orthopedic surgery was performed, using both PubMed and OVID databases were. Study quality was assessed using the modified Jadad Scale. Primary outcomes were pain at 24 and 48 hours and morphine consumption. EVIDENCE SYNTHESIS: Five studies matched the inclusion criteria and were considered of good quality to be included in the review process. All these studies consistently showed a better pain control both at rest and during movement within the first postoperative day, leading to a reduced opioid consumption in patients treated with outpatient continuous regional analgesia. However, only three studies showed these advantages to be sustained longer than the first 24 hours postoperatively. No severe complications were reported. CONCLUSIONS: High-quality evidences about outpatient regional analgesia are scarce. Considering the advantages of continuous peripheral nerve blocks in the inpatient setting more prospective studies assessing also functional recovery are needed to further implement these techniques in the ambulatory setting.

Incidence of postoperative delirium is high even in a population without known risk factors.

PURPOSE: Postoperative delirium is a recognized complication in populations at risk. The aim of this study is to assess the prevalence of early postoperative delirium in a population without known risk factors admitted to the ICU for postoperative monitoring after elective major surgery. The secondary outcome investigated is to identify eventual independent risk factors among demographic data and anesthetic drugs used. METHODS: An observational, prospective study was conducted on a consecutive cohort of patients admitted to our ICU within and for at least 24 h after major surgical procedures. Exclusion criteria were any preexisting predisposing factor for delirium or other potentially confounding neurological dysfunctions. Patients were assessed daily using the confusion assessment method for the ICU scale for 3 days after the surgical procedure. Early postoperative delirium incidence risk factors were then assessed through three different multiple regression models. RESULTS: According to the confusion assessment method for the ICU scale, 28 % of patients were diagnosed with early postoperative delirium. The use of thiopentone was significantly associated with an eight-fold-higher risk for delirium compared to propofol (57.1% vs. 7.1%, RR = 8.0, χ2 = 4.256; df = 1; 0.05 < p < 0.02). CONCLUSION: In this study early postoperative delirium was found to be a very common complication after major surgery, even in a population without known risk factors. Thiopentone was independently associated with an increase in its relative risk.

Safety and effectiveness of bilateral continuous sciatic nerve block for bilateral orthopaedic foot surgery: a cohort study.

BACKGROUND: Severe postoperative pain is a major problem after unilateral and bilateral foot surgery. Continuous regional anaesthesia is often used for unilateral surgery. However, for bilateral surgery, the incidence of complications of continuous bilateral compared with unilateral regional anaesthesia is unknown. OBJECTIVES: To assess the incidence of catheter-related complications of bilateral compared with unilateral continuous regional anaesthesia. DESIGN: A prospective observational study. SETTING: Bellinzona Regional Hospital, a tertiary teaching hospital. PATIENTS: Patients (n = 130) scheduled for elective bilateral or unilateral hallux valgus repair treated with continuous popliteal sciatic nerve block using a continuous infusion of ropivacaine 0.15% at 5 ml h for each popliteal catheter by elastomeric pumps. INTERVENTIONS: The incidence of catheter-related complications, effectiveness, pain levels at rest and with motion, patient satisfaction for the first three postoperative days and the incidence of ambulatory visits or readmissions after discharge were measured. A follow-up for neurological or other complications related to regional anaesthesia was performed 6 to 8 weeks after surgery. MAIN OUTCOME MEASURE: The incidence of catheter-related complications comparing bilateral with unilateral continuous sciatic popliteal nerve block. RESULTS: There were no differences in the incidence of catheter-related complications between the groups. Pain scores at rest and with motion were comparable between the groups. All patients were fit for discharge home 3 days after surgery. Patient satisfaction was similar between the groups. There were no unplanned ambulatory visits or readmissions due to complications in either group. No complications related to regional anaesthesia were reported during the follow-up. CONCLUSION: The complication rate, effectiveness and patient satisfaction of bilateral continuous popliteal sciatic nerve block was comparable with unilateral continuous sciatic popliteal nerve block. The follow-up showed that bilateral continuous sciatic popliteal nerve block does not increase the complication rate. However, an outpatient-based study should confirm these data prior to introduction in the ambulatory setting.

Case report: unusual complication during outpatient continuous regional popliteal analgesia.

PURPOSE: Continuous regional anesthesia applied as pain therapy at home is clinically established standard practice after upper and lower limb surgery. Persistent motor block at discharge or after continuous infusion of local anesthetics, however, might lead to complications related to the insensate extremity. We report a rare case of a foot fracture due to stumbling after continuous sciatic nerve block at home and discuss the related clinical implications. CLINICAL FEATURES: After uncomplicated ambulatory foot surgery under regional anesthesia, a patient was discharged with a continuous sciatic popliteal nerve block for pain therapy at home. After stumbling, the patient remained symptom-free even until catheter removal three days after surgery. Radiography done one week after surgery revealed a styloid fracture of the fifth metatarsal bone. Her subsequent recovery was uneventful. CONCLUSIONS: The true incidence of complications related to falls at home associated with lower extremity blockade remains unknown, as symptoms of possible complications may be masked by the effects of the local anesthetic. However, with increasing use of postoperative regional anesthesia, it is mandatory to develop and adhere to clinical care maps, and to elaborate and teach strategies to further enhance patient safety.

Respiratory variation of intra-abdominal pressure: indirect indicator of abdominal compliance?

OBJECTIVE: To assess if the observed respiratory cycle-related variation in intra-abdominal pressure is reliably quantifiable and a possible indirect indicator of abdominal compliance. Secondary issues were to assess the roles played by respiratory parameters in determining this oscillation and by patients' position in increasing their intra-abdominal pressure. DESIGN AND SETTING: Prospective observational study in a 26-bed medical-surgical intensive care unit. PATIENTS: Sixteen consecutive patients admitted to intensive care for at least 24 h, requiring mechanical ventilation and intra-abdominal pressure monitoring. MEASUREMENTS AND RESULTS: Intra-abdominal pressure was measured with a modified Kron technique; its waveform was recorded and inspiratory and expiratory values were measured during five consecutive respiratory cycles for 5 days, both in the supine and the 30 degrees head-up position. Inspiratory values were significantly higher than expiratory values (p = 0.001) and a correlation was found between their difference and intra-abdominal pressure basal values (p = 0.025). A positive linear relationship was shown between intra-abdominal pressure and the amplitude of its oscillation (r = 0.4), particularly in the subgroup of patients with intra-abdominal hypertension (r = 0.9). Intra-abdominal pressure was lower in patients supine than in the 30 degrees head-up position (p = 0.001). CONCLUSIONS: Respiratory cycle-related variations in intra-abdominal pressure were specifically investigated, quantified and shown as linearly increasing with end-expiratory intra-abdominal pressure; this phenomenon could be explained by patients' abdominal compliance status. Supine posture should be an important consideration in specific patients affected by intra-abdominal hypertension.