Minerva anestesiologica
-
Minerva anestesiologica · Jun 2013
LACTATE or ScvO2 as an endpoint in resuscitation of shock states?
In the current management of critically ill patients, variables such as blood pressure, urine output or central venous pressure guide resuscitative efforts. Unfortunately, global tissue hypoxia may persist leading to multiple organ failure and death. To address tissue well-being, indices such as central venous oxygen saturation (ScvO2) and lactataemia are widely used and are strongly linked to outcome. ⋯ Herein, we review the physiology and rationale for ScvO2 and lactate monitoring. Clinical uses, evidence-based outcome implications and limitations are also examined to aid the clinician in daily practice. Key words: lactate, central venous oxygen saturation, shock, goal-directed therapy.
-
Minerva anestesiologica · Jun 2013
Randomized Controlled Trial Comparative StudyA prospective, randomized controlled trial comparing the left lateral, modified lateral and sitting positions for spinal block characteristics for Cesarean delivery.
Maternal position affects spinal block characteristics. We investigated the effect of lateral, modified lateral and sitting position for spinal anesthesia with 2 mL hyperbaric bupivacaine 0.5% on spinal block characteristics in this prospective, randomized study. ⋯ Onset time (mean ± SD) for sensory block to T5 dermatome for the lateral, modified lateral and sitting groups was 6.8 ± 2.7, 13.6 ± 6.2 and 9.7 ± 5.5 min, respectively; P<0.001. The median (interquartile range) maximum dermatomal level was significantly lower in the modified lateral group (T5[T3-T5]) compared with the lateral (T3[T2-T4]) and sitting (T3[T3-T4]) groups, respectively; P=0.022 and P=0.030, respectively. Three women in the modified lateral group required general anesthesia compared with none in the other groups; P= 0.044. Apgar scores and cord blood pH, PO2 and PCO2 were similar between groups. Conclusion: The modified lateral position with 10 mg of hyperbaric bupivacaine was associated with a slower onset and a lower maximum sensory block necessitating higher requirement for conversion to general anesthesia. It did not offer any advantage over lateral and sitting positions for induction of spinal anesthesia for elective Cesarean delivery and cannot be recommended.
-
Minerva anestesiologica · Jun 2013
Review Meta AnalysisIntrathecal magnesium as analgesic adjuvant for spinal anesthesia: a meta-analysis of randomized trials.
Intrathecal magnesium extends analgesic duration of spinal opioids.
pearl -
Given the low physical solubility of oxygen (O2) in plasma, little value is attached to hyperoxic ventilation (FiO2 1.0) as a modality for improving O2 transport and tissue oxygen supply when hypoxemia (i.e., O2 partial pressure (paO2) <60 mmHg) is absent. Because recent experimental and clinical data conflict with this notion, we used mathematical modeling to reevaluate efficacy of hyperoxic ventilation in improving tissue oxygenation in the absence of hypoxemia by specifying its theoretical efficacy in terms of hemoglobin (Hb) equivalents. ⋯ Hyperoxic ventilation establishes a highly available source of O2 that can be utilized effectively for tissue oxygenation. Although further experimental studies are required to quantify this theoretically calculated amount of utilizable O2, these results suggest that the tissue oxygenation efficacy of hyperoxic ventilation, even in absence of hypoxemia, is grossly underestimated in daily clinical practice.