Regional anaesthesia for major orthopaedic trauma surgery in patients with conservatively managed pneumothoraces

The anaesthetic management of multiple traumatic injuries poses numerous challenges. In this report, we present the cases of two patients with polytrauma including pneumothoraces and multiple rib fractures. The first patient, a 39-year-old man, presented with multiple left upper limb fractures, multiple bilateral rib fractures, bilateral pneumothoraces and fractures of multiple facial and cranial bones. The second patient, a 39-year-old woman, presented with right-sided radial and ulnar fractures, a right-sided pelvic fracture, and multiple right-sided rib fractures with an associated pneumothorax. We used ultrasound-guided superficial cervical plexus, interscalene and supraclavicular blocks in the first case and a combined spinal and epidural after ultrasound-guided fascia iliaca and supraclavicular blocks in the second case. In both cases, the use of multiple regional techniques allowed us to avoid the risks of general anaesthesia in patients with conservatively managed pneumothoraces.

FAS-antisense 1 lncRNA and production of soluble versus membrane Fas in B-cell lymphoma

Impaired Fas-mediated apoptosis is associated with poor clinical outcomes and cancer chemoresistance. Soluble Fas receptor (sFas), produced by skipping of exon 6, inhibits apoptosis by sequestering Fas ligand. Serum sFas is associated with poor prognosis of non-Hodgkin's lymphomas. We found that the alternative splicing of Fas in lymphomas is tightly regulated by a long-noncoding RNA corresponding to an antisense transcript of Fas (FAS-AS1). Levels of FAS-AS1 correlate inversely with production of sFas, and FAS-AS1 binding to the RBM5 inhibits RBM5-mediated exon 6 skipping. EZH2, often mutated or overexpressed in lymphomas, hyper-methylates the FAS-AS1 promoter and represses the FAS-AS1 expression. EZH2-mediated repression of FAS-AS1 promoter can be released by DZNeP (3-Deazaneplanocin A) or overcome by ectopic expression of FAS-AS1, both of which increase levels of FAS-AS1 and correspondingly decrease expression of sFas. Treatment with Bruton's tyrosine kinase inhibitor or EZH2 knockdown decreases the levels of EZH2, RBM5 and sFas, thereby enhancing Fas-mediated apoptosis. This is the first report showing functional regulation of Fas repression by its antisense RNA. Our results reveal new therapeutic targets in lymphomas and provide a rationale for the use of EZH2 inhibitors or ibrutinib in combination with chemotherapeutic agents that recruit Fas for effective cell killing.

Interscalene brachial plexus block for shoulder surgery in a patient with arthrogryposis multiplex congenita

A five-year-old child with severe arthrogryposis multiplex congenita and malnutrition underwent surgery for chronic osteomyelitis of the head of the left humerus. The child had typical features of arthrogryposis multiplex congenita, including a difficult airway. Propofol was used for induction and maintenance. Spontaneous respiration was maintained with a nasal airway. Analgesia was provided with an interscalene brachial plexus block placed using a nerve stimulator. No opioid was given. The child had an uneventful recovery with good postoperative analgesia. The anaesthetic implications of arthrogryposis multiplex congenita are discussed.

Clinical utility of human polymerized hemoglobin as a blood substitute after acute trauma and urgent surgery

We have previously documented the safety of 1 unit (50 gram) of human polymerized hemoglobin (Poly SFH-P) in healthy volunteers. This report describes the first patient trial to assess the therapeutic benefit of Poly SFH-P in acute blood loss. Thirty-nine patients received 1 (n = 14), 2 (n = 2), 3 (n = 15), or 6 (n = 8) units of Poly SFH-P instead of red cells as part of their blood replacement after trauma and urgent surgery. There were no safety issues related to the infusion of Poly SFH-P. The plasma hemoglobin concentration ([Hb]) after the infusion of 6 units (300 gram) of Poly SFH-P was 4.8 +/- 0.8 g/dL (mean +/- SD). Although the red cell [Hb] fell to 2.9 +/- 1.2 g/dL, the total [Hb] was maintained at 7.5 +/- 1.2 g/dL. Poly SFH-P maintained total [Hb], despite the marked fall in red cell [Hb] due to blood loss. The utilization of O2 (extraction ratio) was 27 +/- 16% from the red cells and 37 +/- 13% from the Poly SFH-P. Twenty-three patients (59%) avoided allogeneic transfusions during the first 24 hours after blood loss. Poly SFH-P effectively loads and unloads O2 and maintains total hemoglobin in lieu of red cells after acute blood loss, thereby reducing allogeneic transfusions. Poly SFH-P seems to be a clinically useful blood substitute.

Accelerated erythropoiesis: the hidden benefit of autologous donation

The risks associated with the administration of blood products have increased efforts to avoid homologous transfusions. Preoperative autologous donation has received renewed interest as a method of decreasing homologous transfusion requirements. Autologous donations may also stimulate postoperative erythropoiesis. The purpose of this study is to evaluate the effect of an aggressive autologous donation program on postoperative erythropoiesis. Ten adult male baboons were divided into two groups. The autologous group (n = 5) donated an average of 2 units of blood per week for 5 weeks before operation. The control group (n = 5) had no preoperative treatment. All animals then underwent a laparotomy and exchange transfusion with hetastarch to a final hematocrit of 15 percent. The time required to recover to hematocrits of 20 percent (3.3 vs. 5.7 days, p less than 0.01), 25 percent (7.0 vs. 8.8 days, p less than 0.05), and 30 percent (11.1 vs. 17.7 days, p less than 0.01) was shorter in the autologous group. The autologous group had more intense reticulocytosis during the first 4 postoperative days (p less than 0.03). The data show that participation in an aggressive autologous donation program improves the erythropoietic response to anemia in the postoperative setting. This represents a hidden benefit of preoperative autologous donations and suggests that more aggressive donation schedules may be clinically beneficial. Recognition of that acceleration of erythropoiesis by autologous donation could further reduce the need for transfusion of homologous blood.

Physiologic effects of acute anemia: implications for a reduced transfusion trigger

The risks of transfusion-associated infectious disease have led to a reassessment of transfusion practice, which in turn has resulted in a trend toward the reduction of homologous transfusion. This reduction is primarily due to the initiation of hemotherapy at more severe levels of anemia. The optimum threshold for the initiation of transfusion therapy, or the transfusion trigger (TT), is unknown. The purpose of this study is to evaluate the effects of withholding transfusion or lowering the TT to a hematocrit (Hct) of 15 percent in unanesthetized animals. Nineteen adult baboons underwent a laparotomy to simulate surgical stress. Upon their recovery from anesthesia, hemodynamic measurements were obtained, and the animals underwent an exchange transfusion (ET) with 6-percent hetastarch to a final Hct of 15 percent. After ET, hemodynamic measurements were repeated, and the animals were followed for 2 months. There was no morbidity after ET or during the 2-month observation period. After ET, there was a significant increase in both the cardiac output (3.3 vs. 2.5 L/min, p less than 0.001) and the oxygen extraction ratio (59.9 vs. 38.2%, p less than 0.0001). Oxygen delivery fell after ET (18.9 vs. 11.1 cc/kg/min, p less than 0.001), but there was no significant change in oxygen consumption after ET. The unanesthetized animals adapted well to severe anemia and experienced no adverse effects on their long-term survival in this setting, which suggests that the reduction of the TT to a Hct of 15 percent in normal animals is safe. Adoption of this TT could result in a significant reduction in the requirements for homologous transfusion with its attendant risks.

Pulmonary dysfunction in sepsis: is pulmonary edema the culprit?

Pulmonary dysfunction is a well-recognized sequela of sepsis, which has been quantitated by calculation of intrapulmonary shunt (Qs/Qt) and, more recently, by measurement of extravascular lung water (EVLW). We sought to demonstrate the relationship between Qs/Qt and EVLW in sepsis. Nine pigs were given live E. coli infusions and five control pigs received only crystalloid. Pulmonary artery pressure (PAP), pulmonary artery wedge pressure (PAWP), arterial blood gases (ABG), and mixed venous blood gas levels were measured serially and Qs/QT calculated. EVLW was measured simultaneously using the thermal-green dye technique. The septic group showed increases from baseline in PAP (2.4 X), EVLW (2x), and Qs/Qt (1.6x). Regression analysis of Qs/Qt or EVLW yielded a correlation coefficient of r = 0.48. We concluded that while sepsis can result in both increased EVLW and Qs/Qt, the correlation is not sufficiently strong to account for the increased Qs/Qt on the basis of elevated EVLW alone. The possible relationships of arterial hypoxemia and pulmonary edema, ventilation-perfusion mismatch, and alterations in the normal hypoxic vasoconstrictive response in sepsis are considered.

Changes in lung ultrastructure following heterologous and homologous serum albumin infusion in the treatment of hemorrhagic shock

The object of this study was to compare the ultrastructure pulmonary effects of the infusion of homologous and heterologous serum albumin solution in the treatment of hemorrhagic shock in baboons. Adult baboons subjected to hemorrhagic shock were resuscitated with either baboon serum albumin, human serum albumin, or Ringer's lactate solution. The lungs were fixed in vivo with potassium pyroantimony, a solution which produces electron dense interstitial precipitation of sodium. The lungs from animals resuscitated with baboon serum albumin showed evidence of interstitial edema, including dispersion of collagen fibers, interstitial smudging and increased interstital sodium concentrations. Similar changes were seen following human serum albumin infusions. Lung tissue from animals treated with Ringer's lactate solution showed minimal changes from normal. These results suggest that interstitial pulmonary edema develops after either homologous or heterologous serum albumin infusion in the treatment of hemorrhagic shock in baboons.