title: Small-volume 7.5% NaCl adenosine, lidocaine, and Mg2+ has multiple benefits during hypotensive and blood resuscitation in the pig following severe blood loss: rat to pig translation.
abstract: OBJECTIVE
  Currently, there is no effective small-volume fluid for traumatic hemorrhagic shock. Our objective was to translate small-volume 7.5% NaCl adenosine, lidocaine, and Mg hypotensive fluid resuscitation from the rat to the pig.
  
  
  METHODS
  Pigs (35-40 kg) were anesthetized and bled to mean arterial pressure of 35-40 mm Hg for 90 minutes, followed by 60 minutes of hypotensive resuscitation and infusion of shed blood. Data were collected continuously.
  
  
  METHODS
  University hospital laboratory.
  
  
  METHODS
  Female farm-bred pigs.
  
  
  METHODS
  Pigs were randomly assigned to a single IV bolus of 4 mL/kg 7.5% NaCl + adenosine, lidocaine and Mg (n = 8) or 4 mL/kg 7.5% NaCl (n = 8) at hypotensive resuscitation and 0.9% NaCl ± adenosine and lidocaine at infusion of shed blood.
  
  
  RESULTS
  At 60 minutes of hypotensive resuscitation, treatment with 7.5% NaCl + adenosine, lidocaine, and Mg generated significantly higher mean arterial pressure (48 mm Hg [95% CI, 44-52] vs 33 mm Hg [95% CI, 30-36], p < 0.0001), cardiac index (76 mL/min/kg [95% CI, 63-91] vs 47 mL/min/kg [95% CI, 39-57], p = 0.002), and oxygen delivery (7.6 mL O2/min/kg [95% CI, 6.4-9.0] vs 5.2 mL O2/min/kg [95% CI, 4.4-6.2], p = 0.003) when compared with controls. Pigs that received adenosine, lidocaine, and Mg/adenosine and lidocaine also had significantly lower blood lactate (7.1 mM [95% CI, 5.7-8.9] vs 11.3 mM [95% CI, 9.0-14.1], p = 0.004), core body temperature (39.3°C [95% CI, 39.0-39.5] vs 39.7°C [95% CI, 39.4-39.9]), and higher base excess (-5.9 mEq/L [95% CI, -8.0 to -3.8] vs -11.2 mEq/L [95% CI, -13.4 to -9.1]). One control died from cardiovascular collapse. Higher cardiac index in the adenosine, lidocaine, and Mg/adenosine and lidocaine group was due to a two-fold increase in stroke volume. Left ventricular systolic ejection times were significantly higher and inversely related to heart rate in the adenosine, lidocaine, and Mg/adenosine and lidocaine group. Thirty minutes after blood return, whole-body oxygen consumption decreased in pigs that received adenosine, lidocaine, and Mg/adenosine and lidocaine (5.7 mL O2/min/kg [95% CI, 4.7-6.8] to 4.9 mL O2/min/kg [95% CI, 4.2-5.8]), whereas it increased in controls (4.2 mL O2/min/kg [95% CI, 3.5-5.0] to 5.8 mL O2/min/kg [95% CI, 4.9-5.8], p = 0.02). After 180 minutes, pigs in the adenosine, lidocaine, and Mg/adenosine and lidocaine group had three-fold higher urinary output (2.1 mL//kg/hr [95% CI, 1.2-3.8] vs 0.7 mL//kg/hr [95% CI, 0.4-1.2], p = 0.001) and lower plasma creatinine levels.
  
  
  CONCLUSIONS
  Small-volume resuscitation with 7.5% NaCl + adenosine, lidocaine, and Mg/adenosine and lidocaine provided superior cardiovascular, acid-base, metabolic, and renal recoveries following severe hemorrhagic shock in the pig compared with 7.5% NaCl alone.
authors.affiliation: 1Department of Anesthesiology, Aarhus University Hospital, Aarhus, Denmark. 2Heart and Trauma Research Laboratory, Australian Institute of Tropical Health and Medicine, School of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia. 3Department of Medicine, Mount Sinai School of Medicine, New York, NY. 4Department of Biology, Montclair State University, Montclair, NJ. 5The Cardiothoracic Research Laboratory, Carlyle Fraser Heart Center of Emory University School of Medicine, Atlanta, GA.
authors.forename: Asger
authors.initials: A
authors.lastname: Granfeldt
authors.forename: Hayley L
authors.initials: HL
authors.lastname: Letson
authors.forename: Janus A
authors.initials: JA
authors.lastname: Hyldebrandt
authors.forename: Edward R
authors.initials: ER
authors.lastname: Wang
authors.forename: Pablo A
authors.initials: PA
authors.lastname: Salcedo
authors.forename: Torben K
authors.initials: TK
authors.lastname: Nielsen
authors.forename: Else
authors.initials: E
authors.lastname: Tønnesen
authors.forename: Jakob
authors.initials: J
authors.lastname: Vinten-Johansen
authors.forename: Geoffrey P
authors.initials: GP
authors.lastname: Dobson
mesh_terms: D000241:Adenosine / Q000008:administration & dosage; D000818:Animals; D001810:Blood Volume / Q000187:drug effects; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination / Q000379:methods*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006441:Hemoglobin A / Q000032:analysis; D007022:Hypotension / Q000188:drug therapy* / Q000378:metabolism; D007262:Infusions, Intravenous; D008012:Lidocaine / Q000008:administration & dosage; D008274:Magnesium / Q000008:administration & dosage; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D015532:Rehydration Solutions / Q000494:pharmacology; D012771:Shock, Hemorrhagic / Q000188:drug therapy* / Q000378:metabolism; D012965:Sodium Chloride / Q000008:administration & dosage; D013318:Stroke Volume / Q000187:drug effects; D034421:Sus scrofa; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D015532:Rehydration Solutions; D014665:Vasodilator Agents; D012965:Sodium Chloride; D006441:Hemoglobin A; D008012:Lidocaine; D008274:Magnesium; D000241:Adenosine