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Fluid restriction in novel clinically-relevant model of polytrauma
S32
Critical Care II
(0.5°C/min). Post-operatively, they were monitored for six weeks for bleeding, neurologic/organ dysfunction, cognitive functions, and septic complications. RESULTS: The 6 week survival rates were 87.5%, 87.5% and 75% for groups 1, 2 and 3 respectively (p⬎0.05). One animal in each group died due to acute cardiac failure. One additional animal in group 3 died due to bowel obstruction. All the surviving animals were neurologically intact, displayed normal learning capacity, and had no long-term organ dysfunction. None of the animals had post operative hemorrhage or septic complications. CONCLUSIONS: Profound hypothermia can improve survival in the setting of solid organ, colon, and lethal vascular injuries without an increase in post-operative complication rates.
Resuscitation with normal saline (NS) increased volume requirement, increased cardiac output and decreased systemic vascular resistance compared to lactated ringers (LR) in an uncontrolled hemorrhagic shock model in swine Brandon Tieu MD, T Miko Enomoto MD, Charles Phillips MD, Daniel Hagg MD, Tracy Wiesberg MD, Patrick Muller BS, Martin Schreiber MD Oregon Health & Sciences University, Portland, OR INTRODUCTION: LR and NS solutions are used interchangeably for hemorrhagic shock resuscitation. We hypothesized that physiologic response to resuscitation differs between these solutions. METHODS: Twenty swine were randomized to blinded resuscitation with LR or NS. Animals underwent anesthesia, invasive line placement, celiotomy, splenectomy, and grade V liver injury followed by 30 minutes of uncontrolled hemorrhage. Blood loss was measured. Resuscitation was administered to achieve and maintain baseline mean arterial pressure (MAP). MAP, cardiac output (CO), systemic vascular resistance (SVR), stroke volume (SV) and tissue oxygenation (STO2) were monitored using continuous pulse contour wave analysis. RESULTS: Blood loss was 763⫹⫺206 ml in the NS and 649⫹⫺158 ml in the LR group, p⫽0.183. Animals required 10,901⫹⫺3,820 ml of NS vs. 5,175⫹⫺1,965ml of LR, p⫽0.001. The NS group had a lower MAP at T⫽67–99 min., p ⬍0.05. During resuscitation, NS pigs had a higher heart rate, 128 vs. 100 beats/ min (p⫽0.026), and CO, 5.76 vs. 4.62 L/min (p⫽0.017), while SV remained comparable between groups. SVR was lower in NS pigs, 748 vs. 1,018 (dyne*sec)/cm5 (p⬍0.001). STO2 was similar between groups. Hematocrit was lower in the NS pigs, 12.7⫹⫺3.3%, than LR pigs, 16.6⫹⫺3.6%, p⫽0.029, at the end of the study. Urine output was greater in pigs receiving NS (1,459⫹⫺886 vs. 651⫹⫺392 ml, p⫽0.021). CONCLUSIONS: In an anesthetized swine model of uncontrolled hemorrhagic shock, utilizing MAP as the resuscitation endpoint, use of NS results in greater required volume, decreased SVR and increased cardiac output compared to LR, suggesting significantly different hemodynamic effects.
J Am Coll Surg
Fluid restriction in novel clinically-relevant model of polytrauma Steven A Earle MD, Marc A DeMoya MD, Jennifer E Zuccarelli BA, Kenneth G Proctor PhD University of Miami Miller School of Medicine, Miami, FL INTRODUCTION: Trauma patients frequently suffer multiple severe injuries and hemorrhagic shock is less common, but most models include the opposite pattern. We developed a new model to test the hypothesis that cerebrovascular function is improved with IVF restriction. METHODS: Anesthetized, swine (40–60kg, n⫽33) received severe closed head injury, bilateral lung contusions and hypoventilation for 30min. For 15min, “prehospital” resuscitation in the control group (n⫽5) was ventilatory support and 1L of normal saline (NS). For 15ⱳ90min, additional NS maintained mean arterial pressure (MAP)⬎60mmHg (ER phase). After 90min (ICU phase), mannitol, phenylephrine, plus additional NS were titrated to cerebral perfusion pressure (CPP)⬎70mmHg at a filling pressure ⬎12mmHg. Group 2 (n⫽5) received NS to the same MAP and CPP targets, but filling pressure was 8mmHg. Group 3 (n⫽5) received Hextend, instead of NS, to group 2 targets. Group 4 (n⫽5) received minimal NS and phenylephrine to the same MAP and CPP targets. RESULTS: All groups were similar in baseline conditions. At 30min after injury, MAP⫽55-60mmHg, HR⬎100 b/min, PaO2⬍50 mmHg, PaCO2⬎60mmHg, and Lactate ⬎5mM. Upon resuscitation, these variables, as well as CPP, mixed venous O2, gastric and portal venous O2, cardiac output, and renal blood flow corrected in all groups. However after 4 hours, (see table). Table. Results after 4 hours Group
Brain PO2 (mmHg)
Control
21 ⫾ 7
2 3 4
22 ⫾ 5 28 ⫾ 6 6 ⫾ 1ⴱ
IVF (mL/kg)
UO (mL/kg)
Hct
ICP (mmHg)
BIS (units)
SR ratio (% time)
163 ⫾ 4
56 ⫾ 9
24 ⫾ 1
38 ⫾ 4
35 ⫾ 15
46 ⫾ 20
39 ⫾ 6 31 ⫾ 7ⴱ 32 ⫾ 6ⴱ
29 ⫾ 1 25 ⫾ 2 31 ⫾ 2ⴱ
26 ⫾ 4ⴱ 14 ⫾ 2ⴱ 22 ⫾ 4ⴱ
58 ⫾ 12 62 ⫾ 4 52 ⫾ 13
17 ⫾ 12 0 ⫾ 0ⴱ 19 ⫾ 19
93 ⫾ 27ⴱ 57 ⫾ 10ⴱ 43 ⫾ 2ⴱ
ⴱp⬍0.05 vs. control; UO⫽urine output; BIS⫽bispectral EEG index; SR⫽BIS suppression ratio.
CONCLUSIONS: In a new, clinically-relevant polytrauma simulation, the sequelae of severe TBI were attenuated when IVF was restricted, especially with Hextend, even at the same standard resuscitation endpoints.
Comparison of prolonged hypotensive and normotensive resuscitation strategies in a porcine model of hemorrhagic shock David E Skarda MD, Gregory Beilman MD, Kristine Mulier MS, Michelle Dunning BS University of Minnesota, Minneapolis, MN INTRODUCTION: Hypotensive resuscitation for patients with hemorrhagic shock, including battlefield-wounded soldiers, remains controversial. In the setting of prolonged evacuation times and limited supplies, hypotensive resuscitation has significant potential advantages. We evaluated physiologic and neurologic outcome parameters in a porcine model of hemorrhagic shock and resuscitation to
Critical Care II
(0.5°C/min). Post-operatively, they were monitored for six weeks for bleeding, neurologic/organ dysfunction, cognitive functions, and septic complications. RESULTS: The 6 week survival rates were 87.5%, 87.5% and 75% for groups 1, 2 and 3 respectively (p⬎0.05). One animal in each group died due to acute cardiac failure. One additional animal in group 3 died due to bowel obstruction. All the surviving animals were neurologically intact, displayed normal learning capacity, and had no long-term organ dysfunction. None of the animals had post operative hemorrhage or septic complications. CONCLUSIONS: Profound hypothermia can improve survival in the setting of solid organ, colon, and lethal vascular injuries without an increase in post-operative complication rates.
Resuscitation with normal saline (NS) increased volume requirement, increased cardiac output and decreased systemic vascular resistance compared to lactated ringers (LR) in an uncontrolled hemorrhagic shock model in swine Brandon Tieu MD, T Miko Enomoto MD, Charles Phillips MD, Daniel Hagg MD, Tracy Wiesberg MD, Patrick Muller BS, Martin Schreiber MD Oregon Health & Sciences University, Portland, OR INTRODUCTION: LR and NS solutions are used interchangeably for hemorrhagic shock resuscitation. We hypothesized that physiologic response to resuscitation differs between these solutions. METHODS: Twenty swine were randomized to blinded resuscitation with LR or NS. Animals underwent anesthesia, invasive line placement, celiotomy, splenectomy, and grade V liver injury followed by 30 minutes of uncontrolled hemorrhage. Blood loss was measured. Resuscitation was administered to achieve and maintain baseline mean arterial pressure (MAP). MAP, cardiac output (CO), systemic vascular resistance (SVR), stroke volume (SV) and tissue oxygenation (STO2) were monitored using continuous pulse contour wave analysis. RESULTS: Blood loss was 763⫹⫺206 ml in the NS and 649⫹⫺158 ml in the LR group, p⫽0.183. Animals required 10,901⫹⫺3,820 ml of NS vs. 5,175⫹⫺1,965ml of LR, p⫽0.001. The NS group had a lower MAP at T⫽67–99 min., p ⬍0.05. During resuscitation, NS pigs had a higher heart rate, 128 vs. 100 beats/ min (p⫽0.026), and CO, 5.76 vs. 4.62 L/min (p⫽0.017), while SV remained comparable between groups. SVR was lower in NS pigs, 748 vs. 1,018 (dyne*sec)/cm5 (p⬍0.001). STO2 was similar between groups. Hematocrit was lower in the NS pigs, 12.7⫹⫺3.3%, than LR pigs, 16.6⫹⫺3.6%, p⫽0.029, at the end of the study. Urine output was greater in pigs receiving NS (1,459⫹⫺886 vs. 651⫹⫺392 ml, p⫽0.021). CONCLUSIONS: In an anesthetized swine model of uncontrolled hemorrhagic shock, utilizing MAP as the resuscitation endpoint, use of NS results in greater required volume, decreased SVR and increased cardiac output compared to LR, suggesting significantly different hemodynamic effects.
J Am Coll Surg
Fluid restriction in novel clinically-relevant model of polytrauma Steven A Earle MD, Marc A DeMoya MD, Jennifer E Zuccarelli BA, Kenneth G Proctor PhD University of Miami Miller School of Medicine, Miami, FL INTRODUCTION: Trauma patients frequently suffer multiple severe injuries and hemorrhagic shock is less common, but most models include the opposite pattern. We developed a new model to test the hypothesis that cerebrovascular function is improved with IVF restriction. METHODS: Anesthetized, swine (40–60kg, n⫽33) received severe closed head injury, bilateral lung contusions and hypoventilation for 30min. For 15min, “prehospital” resuscitation in the control group (n⫽5) was ventilatory support and 1L of normal saline (NS). For 15ⱳ90min, additional NS maintained mean arterial pressure (MAP)⬎60mmHg (ER phase). After 90min (ICU phase), mannitol, phenylephrine, plus additional NS were titrated to cerebral perfusion pressure (CPP)⬎70mmHg at a filling pressure ⬎12mmHg. Group 2 (n⫽5) received NS to the same MAP and CPP targets, but filling pressure was 8mmHg. Group 3 (n⫽5) received Hextend, instead of NS, to group 2 targets. Group 4 (n⫽5) received minimal NS and phenylephrine to the same MAP and CPP targets. RESULTS: All groups were similar in baseline conditions. At 30min after injury, MAP⫽55-60mmHg, HR⬎100 b/min, PaO2⬍50 mmHg, PaCO2⬎60mmHg, and Lactate ⬎5mM. Upon resuscitation, these variables, as well as CPP, mixed venous O2, gastric and portal venous O2, cardiac output, and renal blood flow corrected in all groups. However after 4 hours, (see table). Table. Results after 4 hours Group
Brain PO2 (mmHg)
Control
21 ⫾ 7
2 3 4
22 ⫾ 5 28 ⫾ 6 6 ⫾ 1ⴱ
IVF (mL/kg)
UO (mL/kg)
Hct
ICP (mmHg)
BIS (units)
SR ratio (% time)
163 ⫾ 4
56 ⫾ 9
24 ⫾ 1
38 ⫾ 4
35 ⫾ 15
46 ⫾ 20
39 ⫾ 6 31 ⫾ 7ⴱ 32 ⫾ 6ⴱ
29 ⫾ 1 25 ⫾ 2 31 ⫾ 2ⴱ
26 ⫾ 4ⴱ 14 ⫾ 2ⴱ 22 ⫾ 4ⴱ
58 ⫾ 12 62 ⫾ 4 52 ⫾ 13
17 ⫾ 12 0 ⫾ 0ⴱ 19 ⫾ 19
93 ⫾ 27ⴱ 57 ⫾ 10ⴱ 43 ⫾ 2ⴱ
ⴱp⬍0.05 vs. control; UO⫽urine output; BIS⫽bispectral EEG index; SR⫽BIS suppression ratio.
CONCLUSIONS: In a new, clinically-relevant polytrauma simulation, the sequelae of severe TBI were attenuated when IVF was restricted, especially with Hextend, even at the same standard resuscitation endpoints.
Comparison of prolonged hypotensive and normotensive resuscitation strategies in a porcine model of hemorrhagic shock David E Skarda MD, Gregory Beilman MD, Kristine Mulier MS, Michelle Dunning BS University of Minnesota, Minneapolis, MN INTRODUCTION: Hypotensive resuscitation for patients with hemorrhagic shock, including battlefield-wounded soldiers, remains controversial. In the setting of prolonged evacuation times and limited supplies, hypotensive resuscitation has significant potential advantages. We evaluated physiologic and neurologic outcome parameters in a porcine model of hemorrhagic shock and resuscitation to