OBJECTIVE: This study was designed to evaluate the effects of terlipressin versus fluid resuscitation with normal saline, hypertonic saline or hypertonic-hyperoncotic hydroxyethyl starch, on hemodynamics, metabolics, blood loss and short-term survival in hemorrhagic shock. METHOD: Twenty-nine pigs were subjected to severe liver injury and treated 30 min later with either: (1) 2 mg terlipressin in a bolus, (2) placebo-treated controls, (3) 4 mL/kg 7.5% hypertonic NaCl, (4) 4 mL/kg 7.2% hypertonic-hyperoncotic hydroxyethyl starch 200/0.5, or (5) normal saline at three times lost blood volume. RESULTS: The overall mortality rate was 69%. Blood loss was significantly higher in the hypertonic-hyperoncotic hydroxyethyl starch and normal saline groups than in the terlipressin, hypertonic NaCl and placebo-treated controls groups (p<0.005). Hyperkalemia (K>5 mmol/L) before any treatment occurred in 66% of the patients (80% among non-survivors vs. 22% among survivors, p=0.019). Post-resuscitation hyperkalemia occurred in 86.66% of non-survivors vs. 0% of survivors (p<0.001). Hyperkalemia was the first sign of an unsuccessful outcome for the usual resuscitative procedure and was not related to arterial acidemia. Successfully resuscitated animals showed a significant decrease in serum potassium levels relative to the baseline value. CONCLUSION: Hyperkalemia accompanies hemorrhagic shock and, in addition to providing an early sign of the acute ischemic insult severity, may be responsible for cardiac arrest related to hemorrhagic shock.

Neste estudo testamos a hipótese de que os efeitos benéficos decorrentes da administração da solução salina hipertônica (NaCl 7,5%, 4 mL/kg) sobre a hemodinâmica sistêmica e cerebral na hipertensão intracraniana e no choque hemorrágico, possam atenuar a diminuição da pressão de perfusão cerebral que freqüentemente acompanha o transplante do fígado para hepatite fulminante. MÉTODO: Foram estudados 10 pacientes com hepatite fulminante em encefalopatia grau IV e monitorização de pressão intracraniana submetidos ao transplante do fígado. A hemodinâmica sistêmica e cerebral de 3 pacientes que receberam solução salina hipertônica durante a fase anepática (Grupo SSH) foi analisada comparando com os dados obtidos de 7 pacientes transplantados anteriormente nas mesmas condições (Grupo Controle). Os valores de pressão intracraniana máxima e a correspondente pressão arterial média foram coletados em quatro tempos: (T1) nos últimos 10 min da fase de disseccão, (T2) nos primeiros 10 minutos da fase anepática, (T3) no final da fase anepática e (T4) nos primeiros 5 min da reperfusão RESULTADO: Imediatamente após a infusão da solução salina hipertônica a pressão intracraniana diminuiu 50,4%. Nos primeiros 5 min da reperfusão a pressão intracraniana no Grupo SSH se manteve estável e todos os pacientes apresentavam pressão intracraniana menor que 20 mmHg enquanto no Grupo Controle a pressão intracraniana aumentou 46,5% (p<0,001). O Grupo SSH apresentou maior estabilidade hemodinâmica, nos primeiros 5 min da reperfusão hepática, a pressão arterial média no Grupo SSH aumentou 21,1% e no Grupo Controle diminuiu 11,1% (p<0,001). Nos primeiros 5 min da reperfusão a pressão de perfusão cerebral no Grupo SSH aumentou 28,3% e no Grupo Controle diminuiu 28,5% (p< 0,001). A natremia no final da fase anepáica e após 3 horas da reperfusão foi significativamente maior no Grupo SSH (153.00 ± 2.66 and 149.00 ± 1.73 mEq/L) que no Grupo Controle (143.71 ± 3.30 and 142.43 ± 1.72 mEq/L), p=0.003 e p< 0.001 respectivamente. CONCLUSÃO: Estes resultados sugerem que a solução salina hipertônica pode ser utilizada com sucesso como medida neuroprotetora no transplante de fígado para hepatite fulminante, promovendo diminuição efetiva da pressão intracraniana e estabilidade cardiocirculatória, proporcionando aumento sustentado da PPC durante a cirurgia.

During orthotopic liver transplantation for fulminant hepatic failure, some patients may develop sudden deterioration of cerebral perfusion and oxygenation, mainly due to increased intracranial pressure and hypotension, which are likely responsible for postoperative neurological morbidity and mortality. In the present study, we hypothesized that the favorable effects of hypertonic saline solution (NaCl 7.5%, 4 mL/kg) infusion on both systemic and cerebral hemodynamics, demonstrated in laboratory and clinical settings of intracranial hypertension and hemorrhagic shock resuscitation, may attenuate the decrease in cerebral perfusion pressure that often occurs during orthotopic liver transplantation for fulminant hepatic failure. METHODS: 10 patients with fulminant hepatic failure in grade IV encephalopathy undergoing orthotopic liver transplantation with intracranial pressure monitoring were included in this study. The effect on cerebral and systemic hemodynamics in 3 patients who received hypertonic saline solution during anhepatic phase (HSS group) was examined, comparing their data with historical controls obtained from surgical procedure recordings in 7 patients (Control group). The maximal intracranial pressure and the corresponding mean arterial pressure values were collected in 4 time periods: (T1) the last 10 min of the dissection phase, (T2) the first 10 minutes at the beginning of anhepatic phase, (T3) at the end of the anhepatic phase, and (T4) the first 5 minutes after graft reperfusion. RESULTS: Immediately after hypertonic saline solution infusion, intracranial pressure decreased 50.4%. During the first 5 min of reperfusion, the intracranial pressure remained stable in the HSS group, and all these patients presented an intracranial pressure lower than 20 mm Hg, while in the Control group, the intracranial pressure increased 46.5% (P < 0.001). The HSS group was the most hemodynamically stable; the mean arterial pressure during the first 5 min of reperfusion increased 21.1% in the HSS group and decreased 11.1% in the Control group (P < 0.001). During the first 5 min of reperfusion, cerebral perfusion pressure increased 28.3% in the HSS group while in the Control group the cerebral perfusion pressure decreased 28.5% (P < 0.001). Serum sodium at the end of the anhepatic phase and 3 hours after reperfusion was significantly higher in the HSS group (153.00 ± 2.66 and 149.00 ± 1.73 mEq/L) than in the Control group (143.71 ± 3.30 and 142.43 ± 1.72 mEq/L), P = 0.003 and P < 0.001 respectively. CONCLUSION: Hypertonic saline solution can be successfully used as an adjunct in the neuroprotective strategy during orthotopic liver transplantation for fulminant hepatic failure, reducing intracranial pressure while restoring arterial blood pressure, promoting sustained increase in the cerebral perfusion pressure.