ABSTRACT
BACKGROUND AND OBJECTIVES: Haemoglobin threshold for transfusion has been significantly decreased, but haemoglobin plasma concentration may not be sufficient to assess the need of red-blood-cell (RBC) transfusion. Central venous oxygen saturation (ScvO2 ) is a clue of metabolic matching between O2 transport and consumption, which could help to assess when transfusion is appropriate once anaemia has been diagnosed in ICU patients. MATERIALS AND METHODS: Adult patients admitted consecutively to a cardiothoracic and vascular ICU were included in a prospective, observational and single-centre study over a 6-month period (September 2014 to February 2015), provided they were transfused with RBC. Patients with active bleeding or in unstable condition were excluded. Haemoglobin and ScvO2 were collected through a central venous catheter before and after transfusion. In order to identify a ScvO2 threshold, analysis of ScvO2 changes after transfusion was performed. RESULTS: Fifty-three patients received 100 RBC transfusions. Haemoglobin at the time of transfusion was 7·2 g/dl [6·8-7·7], while ScvO2 was 66·9% [60-73]. A 5% increase in ScvO2 after transfusion has the best specificity and positive predictive values, with a ScvO2 threshold of 65%. After transfusion (RBC units, 2 [1-2]), ScvO2 increased only in patients with ScvO2 ≤65%, from 58% [53-62] to 69% [64-73] (P < 0·001). CONCLUSION: In anaemic patients, RBC transfusion induced a significant increase in ScvO2 , provided it was low before transfusion. A 65% cut-off value of ScvO2 before transfusion showed good specificity and good positive predictive value for a 5% increase after transfusion.
Subject(s)
Anemia/therapy , Critical Care/methods , Erythrocyte Transfusion/methods , Oxygen/blood , Aged , Erythrocyte Transfusion/adverse effects , Female , Humans , Male , Middle Aged , Oxyhemoglobins/metabolismABSTRACT
UNLABELLED: Femoral shaft or hip surgeries are very painful for children. We conducted both computed tomographic (CT) and clinical prospective studies to define new landmarks in children and to evaluate the effectiveness of continuous psoas compartment blocks (CPCBs) using disposable elastomeric pumps. In a preliminary CT scan study of 20 patients, the plexus depth was correlated to patient age and the optimal point of puncture for CPCB was three-quarters of the distance from the spinous process of L4 to a line parallel to the spinal column passing through the posterior superior iliac spine. In a subsequent prospective series, a CPCB was administered before surgery to 15 children for pain relief after femoral and hip osteotomies. After general anesthesia, a 0.5 mL/kg bolus of a mixture of 1% lidocaine with epinephrine (1/200.000) and 0.5% ropivacaine was injected through the CPCB catheter. After contrast media assessment of the catheter location, a disposable pump (Infusor LV); Baxter, Paris, France) with 0.2% ropivacaine was connected and pump flow was adjusted to the patient's weight (0.2 mg x kg(-1) x h(-1)). Postoperative pain was evaluated using a visual analog scale or the Children and Infants Postoperative Pain Score at hour H1, H6, H12, H18, H24, H36, and H48, and in terms of rescue analgesia, adverse events, and motor blocks. All blocks were effective during surgery. Postoperative analgesia was excellent. The median pain scores were 1 for H1 and 0 beginning H6. The motor blockade was minimal before 24 h and absent thereafter. No major adverse event was noted. Parents of 93% of the children were satisfied. We conclude that postoperative analgesia with CPCB is a very effective technique in children after major proximal lower limb orthopedic surgery. The CT scan landmarks described in this study were more medial than the conventional landmarks used in the literature. IMPLICATIONS: Continuous psoas compartment blocks provide optimal pain relief in children after major orthopedic surgery without major adverse events. The landmarks used, defined in a preliminary computed tomographic scan study, were more medial than conventional landmarks.
