Comparison of the effectiveness of ultrasound-guided versus fluoroscopy-guided medial lumbar bundle branch block on pain related to lumbar facet joints: a multicenter randomized controlled non-inferiority study.

BACKGROUND: The aim of this multicenter randomized interventional prospective study was to compare the ultrasound (US)-guided lumbar medial branch block (LMBB) with the fluoroscopy (FS)-guided LMBB in terms of analgesic efficacy and disability in the setting of the treatment of pain arising from the lumbar facet joints (LFJ). METHODS: Fifty adults with a "LFJ" syndrome were randomized into two groups: in group FS, fluoroscopic-guidance was used to block the medial branch at three lumbar levels (L3-L4, L4-L5 and L5-S1); in group US, same blocks were performed under ultrasound. Needle transverse approach was used with both techniques. Effects of these procedures were assessed with a Visual Analogue Pain Scale (VAPS), the Oswestry Disability Index (ODI) and the Duke's Activity Status Index (DASI) scale, before the treatment, 1 week and 1 month after. Hospital Anxiety and Depression Scale (HADS) score was also collected before the procedure. Analysis of variance, one (for non-inferiority) and two-sided Mann-Whitney tests and Chi-square tests were performed. RESULTS: LMBB under US-guidance was not inferior to FS-guidance (P = 0.047) in terms of VAPS, ODI and DASI at 1 week and 1 month. Duration of techniques and HADS were similar between groups (=0.34; p = 0.59). CONCLUSIONS: The medial lumbar bundle branch block under ultrasound-guidance is not inferior to the fluoroscopy-guidance procedure in effectively alleviating pain arising from the facet joints. Considering that this ultrasound technique has the benefit of an irradiation-free, real-time procedure, it can be considered as an effective alternative to the fluoroscopy-guided technique.

Pleth variability index versus pulse pressure variation for intraoperative goal-directed fluid therapy in patients undergoing low-to-moderate risk abdominal surgery: a randomized controlled trial.

BACKGROUND: Goal-directed fluid therapy (GDFT) based on dynamic indicators of fluid responsiveness has been shown to decrease postoperative complications and hospital length of stay (LOS) in patients undergoing major abdominal surgery. The usefulness of this approach still needs to be clarified in low-to-moderate risk abdominal surgery. Both pulse-pressure variation (PPV) and pleth variability index (PVI) can be used to guide GDFT strategies. The objective of this prospective randomized controlled trial was to determine if the use of PVI guided GDFT, when compared to PPV guided GDFT, would lead to similar hospital LOS in patients undergoing low-to-moderate risk surgery. Secondary outcomes included amount of fluid administered and incidence of postoperative complications. METHODS: Patients were randomized into either PVI or PPV guided GDFT groups. Both received a baseline 2 ml kg- 1 h- 1 Lactated Ringer infusion. Additional fluid boluses consisted of 250 mL of colloid that was infused over a 10 min period if PVI was > 15% or PPV was > 13% for at least five minutes. The primary outcome was to determine if hospital LOS, which was defined as the number of days from surgery up to the day the surgeon authorized hospital discharge, was equivalent between the two groups. RESULTS: A total of 76 patients were included and they were randomized into two groups of 38 patients. Baseline characteristics were similar in both groups. Both PVI and PPV guided GDFT strategies were equivalent for the primary outcome of LOS (median [interquartile range]) (days) 2.5 [2.0-3.3] vs. 3.0 [2.0-5.0], p = 0.230, respectively. Fluids infused, postoperative complications, and all other outcomes were not different between groups. CONCLUSION: In patients undergoing low-to-moderate risk abdominal surgery, PVI seems to guide GDFT similarly to PPV in regards to hospital LOS, amount of fluid, and incidence of postoperative complications. However, in low-risk patients undergoing these surgical procedures optimizing stroke volume may have limited impact on outcome. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02908256 , September 2016, retrospectively registered.

Effect of pneumoperitoneum on dynamic variables of fluid responsiveness (Delta PP and PVI) during Trendelenburg position.

BACKGROUND AND AIMS: Pulse pressure variation (ΔPP) is considered as one of the best predictors of fluid responsiveness in patients under mechanical ventilation. Pleth Variability Index (PVI) has been proposed as a noninvasive alternative. However, pneumoperitoneum has been recently suggested as a limitation to their interpretation. The aim of this study was to compare changes in ΔPP and PVI related to autotransfusion associated with a Trendelenburg maneuver before and during pneumoperitoneum. METHODS: 50 patients undergoing elective abdominal laparoscopic surgery were enrolled in this prospective observational study. All patients were equipped with an invasive radial artery catheter and a PVI probe. After obtaining a stable signal with both ΔPP and PVI, baseline values were recorded, before and after head-down tilts of 10°, with or without abdominal insufflation (10-12 mmHg). All measurements were made before any fluid challenge under standardized anaesthesia, while patients were paralyzed and mechanically ventilated with 8 mL/kg tidal volume. RESULTS: Changes in ΔPP and PVI associated with the Trendelenburg maneuver before and after insufflation of the pneumoperitoneum were significantly different (P < 0.001). In baseline conditions, the Trendelenburg maneuver was associated with a significant decrease in heart rate while mean arterial pressure remained unchanged. Both ΔPP and PVI decreased. After insufflation of the pneumoperitoneum, the Trendelenburg maneuver was associated with a significant decrease in heart rate and ΔPP and an increase in mean arterial pressure while PVI remained unchanged. CONCLUSION: Pneumoperitoneum did not alter the response of ΔPP to autotransfusion associated with the Trendelenburg maneuver, which was not the case for the PVI. This latter decreased during Trendelenburg maneuver performed alone and remained unchanged during Trendelenburg maneuver performed after insufflation of the pneumoperitoneum.

Does infusion of colloid influence the occurrence of postoperative nausea and vomiting after elective surgery in women?

BACKGROUND: The impact of the type of fluid on postoperative nausea and vomiting (PONV) is not well defined. In this study we investigated the effects of colloids or crystalloids on PONV when given in addition to a background minimal crystalloid infusion in a female population of surgical patients. METHODS: This prospective, randomized, double-blind study included 115 women undergoing gynecological or breast surgery who were randomly allocated to receive hydroxyethyl starch (HES) 130/0.4 or normal saline in addition to a fixed background infusion of 5% dextrose in 0.45% saline at a flow rate of 0.5 mL x kg(-1) x h(-1). A bolus of 500 mL of the study fluid (HES or normal saline) was infused before the induction of anesthesia, followed by a continuous infusion of 1 mL x kg(-1) x h(-1) adjustable according to hemodynamic needs. The primary outcome variable was the incidence of PONV during the 24 h postoperative period. Secondary end points were the need for antiemetic rescue therapy, incidence of hypotensive episodes, pain scores, and need for additional analgesia. RESULTS: Nausea occurred in 11 of 56 patients who received HES and in 11 of 58 patients who received saline (P > 0.05). There were no differences between groups in the incidence of vomiting. There were no differences between the groups regarding antiemetic rescue therapy, hypotensive episodes, pain scores, or need for opioids. CONCLUSIONS: In surgical procedures with minimal blood loss and minimal fluid shifts, the type of fluid replacement administered (colloid vs 0.9% normal saline) has minimal effect on the incidence of PONV.