The Disposition of Radiocontrast in the Interscalene Space in Healthy Volunteers.

BACKGROUND: We measured the spread of radiocontrast in the interscalene space after injection under low (<15 psi) and high (>20 psi) pressures. METHODS: Nine healthy volunteers received ultrasound-guided injections of 10 mL radio-opaque NaCl 0.9% in both interscalene spaces. Spread of injectate as assessed by computed tomography scan and discomfort on injection were recorded. RESULTS: Under both opening pressure conditions, injectate contacted 3 brachial plexus roots and spilled over the surface of the anterior and/or middle scalene muscles underneath the cervical fascia. CONCLUSIONS: Regardless of injection pressure, the interscalene space was filled with 10 mL of radiocontrast injectate.

Following Evidence-Based Recommendations for Perioperative Pain Management after Cesarean Section Is Associated with Better Pain-Related Outcomes: Analysis of Registry Data.

Women who have had a Cesarean Section (CS) frequently report severe pain and pain-related interference. One reason for insufficient pain treatment might be inconsistent implementation of evidence-based guidelines. We assessed the association between implementing three elements of care recommended by guidelines for postoperative pain management and pain-related patient-reported outcomes (PROs) in women after CS. The analysis relied on an anonymized dataset of women undergoing CS, retrieved from PAIN OUT. PAIN OUT, an international perioperative pain registry, provides clinicians with treatment assessment methodology and tools for patients to assess multi-dimensional pain-related PROs on the first postoperative day. We examined whether the care included [i] regional anesthesia with a neuraxial opioid OR general anesthesia with wound infiltration or a Transvesus Abdominis Plane block; [ii] at least one non-opioid analgesic at the full daily dose; and [iii] pain assessment and recording. Credit for care was given only if all three elements were administered (= "full"); otherwise, it was "incomplete". A "Pain Composite Score-total" (PCStotal), evaluating outcomes of pain intensity, pain-related interference with function, and side-effects, was the primary endpoint in the total cohort (women receiving GA and/or RA) or a sub-group of women with RA only. Data from 5182 women was analyzed. "Full" care was administered to 20% of women in the total cohort and to 21% in the RA sub-group. In both groups, the PCStotal was significantly lower compared to "incomplete" care (p < 0.001); this was a small-to-moderate effect size. Administering all three elements of care was associated with better pain-related outcomes after CS. These should be straightforward and inexpensive for integration into routine care after CS. However, even in this group, a high proportion of women reported poor outcomes, indicating that additional work needs to be carried out to close the evidence-practice gap so that women who have undergone CS can be comfortable when caring for themselves and their newborn.

Low-dose droperidol (≤1 mg or ≤15 µg kg-1) for the prevention of postoperative nausea and vomiting in adults: quantitative systematic review of randomised controlled trials.

CONTEXT: Droperidol is widely used for the prevention of postoperative nausea and vomiting (PONV) in European countries. It is unclear how efficacious low-dose droperidol is in the prevention of PONV. OBJECTIVES: To test the efficacy of low-dose droperidol in the prevention of PONV in adults and to test for dose-responsiveness. DESIGN: Systematic review of randomised controlled trials with meta-analyses. DATA SOURCES: Comprehensive search in electronic databases (Medline, Embase, Central) up to June 2011. Additional trials were obtained from bibliographies of retrieved reports. No language restriction was applied. ELIGIBILITY CRITERIA: Randomised trials testing prophylactic intravenous droperidol ≤1 mg or ≤15 µg kg compared with placebo (or no treatment) in adults undergoing general anaesthesia and reporting on PONV. RESULTS: We analysed 25 trials (2957 patients). Doses varied from 0.25 to 1.0 mg. For prevention of early nausea (within 6 h postoperatively), relative risk (RR) was 0.45 (95% CI, 0.35 to 0.58); number needed to treat (NNT) was 7, 4, and 2 for low, medium and high baseline risk (i.e. control event rate 25, 50, 75%). For prevention of early vomiting, RR was 0.65 (95% CI, 0.57 to 0.74), NNT 11, 6, and 4. For prevention of late nausea (within 24 h), RR was 0.74 (95% CI, 0.62 to 0.87), NNT 15, 8, and 5. For prevention of late vomiting, RR was 0.61 (95% CI, 0.47 to 0.80), NNT 10, 5, and 3. Droperidol decreased the risk of headache but increased the risk of restlessness. For these outcomes there was no evidence of dose-responsiveness. There were no differences in the incidences of sedation or dizziness. Two patients receiving droperidol 0.625 mg had extrapyramidal symptoms. Cardiac toxicity data were not reported. CONCLUSION: Prophylactic doses of droperidol of 1 mg or below are antiemetic. Because adverse drug reactions are likely to be dose-dependent, there is an argument to stop using doses of more than 1 mg.

Acid-base status and hemodynamic stability during propofol and sevoflurane-based anesthesia in patients undergoing uncomplicated intracranial surgery.

Propofol anesthesia may induce metabolic disturbances and sevoflurane anesthesia arterial hypotension. This study compares both techniques regarding acid-base and hemodynamic status during intracranial surgery. Sixty-one patients were randomized into 2 groups according to anesthesia maintenance, a propofol group (n=30), and a sevoflurane group (n=31). The anesthesia protocol including rocuronium and remifentanil infusion was otherwise similar in both groups. Arterial blood samples were drawn every 2 hours during the procedure and upon arrival in the intensive care unit to assess acid-base status. The number of hypotensive and hypertensive events served to assess hemodynamic stability. Metabolic acidosis was more frequent during propofol than sevoflurane anesthesia (7 out of 29 and 1 out of 31, P=0.02). Its severity was linearly correlated with lactate concentration (R=0.32), total dose of propofol (R=0.2), and length of procedure (R=0.28). Hyperlactacidemia was also observed during sevoflurane anesthesia, but without acidosis. Hypertension occurred more frequently during propofol than sevoflurane anesthesia (13 out of 30 vs. 1 out of 31, P<0.001), particularly in patients with a past medical history of hypertension. Higher remifentanil infusion rates reduced the risk of hypertension. Conversely, sevoflurane anesthesia favored arterial hypotension (22 out of 31 vs. 12 out of 30, P=0.015). Preoperative morning administration of antihypertensive medications to patients with a history of arterial hypertension was associated with a low probability of hypertensive events, at the cost of more frequent hypotension. In conclusion, propofol anesthesia for intracranial surgery is more frequently associated with lactic acidosis and hypertension; sevoflurane anesthesia may favor arterial hypotension.