Publique en esta revista
Información de la revista
Vol. 38. Núm. 5.Junio - Julio 2014
Páginas 271-336
Compartir
Compartir
Descargar PDF
Más opciones de artículo
Visitas
1449
Vol. 38. Núm. 5.Junio - Julio 2014
Páginas 271-336
Original
DOI: 10.1016/j.medin.2013.04.005
Acceso a texto completo
Protein C zymogen in adults with severe sepsis or septic shock
Zimógeno de proteína C en adultos con sepsis grave o choque séptico
Visitas
1449
M. Crivellari, S. Silvetti, C. Gerli, G. Landoni??
Autor para correspondencia
landoni.giovanni@hsr.it

Corresponding author.
, A. Franco, T. Bove, F. Pappalardo, A. Zangrillo
Department of Anesthesia and Intensive Care, San Raffaele Scientific Institute, Milano, Italy
Este artículo ha recibido
1449
Visitas
Información del artículo
Resumen
Texto Completo
Bibliografía
Descargar PDF
Estadísticas
Figuras (2)
Tablas (1)
Table 1. Changes in laboratory variables throughout protein C concentrate administration.
Abstract
Introduction

Activated protein C is associated with a risk of bleeding and its effects on survival in septic shock patients are questionable. Protein C zymogen has no risk of bleeding and improves the outcome of patients with septic shock. We hereby describe the largest published case series of adult patients receiving protein C zymogen.

Design, setting and participants

A prospective study on 23 adult patients with severe sepsis or septic shock, two or more organ failures and at high risk for bleeding, treated with protein C zymogen (50IU/kg bolus followed by continuous infusion of 3IU/kg/h for 72h).

Results

The Z-test evidenced a significant reduction between the expected mortality (53%) and the observed mortality 30% (Z value=1.99, p=0.046) in our sample population. Protein C levels increased from 34±18% to 66±22% at 6h after PC bolus (p<0.001), and kept on increasing during 72h of administration (p<0.001 to baseline). Sequential Organ Failure Assessment (SOFA), score of organ dysfunction, decreased from baseline to 7 days after administration of protein C from 14±2 to 7±4 (p<0.001). No adverse event drug related was noted.

Conclusion

Protein C zymogen administration is safe and its use in septic patients should be investigated through a randomized controlled trial.

Keywords:
Protein C zymogen
Bleeding
Sepsis
Intensive care
Critical care
Resumen
Introducción

La proteína C activada se asocia a un elevado riesgo de hemorragia, y sus efectos sobre la supervivencia en los pacientes con choque séptico son cuestionables. El zimógeno de proteína C no presenta ningún riesgo de hemorragia, y mejora los resultados en los pacientes con choque séptico. Describimos la serie de casos más amplia publicada de pacientes adultos tratados con zimógeno de proteína C.

Diseño, ámbito y participantes

Se ha llevado a cabo un estudio prospectivo en el que han participado 23 adultos con sepsis grave o choque séptico, 2 o más fallos orgánicos, y un elevado riesgo de hemorragia, tratados con zimógeno de proteína C (dosis en bolo de 50UI/kg seguida de una infusión continua de 3UI/kg/h durante 72h).

Resultados

La prueba Z puso de manifiesto una disminución significativa entre la mortalidad prevista (53%), y la mortalidad observada 30% (valor Z=1,99; p=0,046) en nuestra serie. Las concentraciones de proteína C incrementaron de 34±18% a 66±22% a las 6h de la dosis en bolo (p<0,001), y siguieron incrementando durante las 72h siguientes a la administración (p<0,001 respecto a la situación basal). La puntuación en la evaluación secuencial del fallo orgánico (SOFA) disminuyó entre la situación basal, y 7 días después de la administración de proteína C de 14±2 a 7±4 (p<0,001). No se registraron reacciones farmacológicas adversas.

Conclusión

El zimógeno de proteína Z debería investigarse su utilización en los pacientes con sepsis mediante un estudio aleatorizado y controlado.

Palabras clave:
Zimógeno de proteína C
Hemorragia
Sepsis
Cuidados intensivos
Cuidados críticos
Texto Completo
Introduction

Severe sepsis and septic shock are life-threatening medical emergencies and are among the most significant challenges in critical care. Mortality rates approach 30–50%, and can be as high as 90% when multiple organ dysfunctions ensue.1,2 Improvement in survival rates was achieved through early broad-spectrum antibiotic administration, organ supportive therapy, and, until recently, through Recombinant Human Activated Protein C (rhAPC) in selected patients at low risk of bleeding. A recent randomized study showed that rhAPC did not significantly reduce mortality at 28 or 90 days, as compared with placebo, in patients with septic shock.3

Protein C (PC) is the vitamin K-dependent zymogen of a serine protease with antithrombotic, anti-inflammatory, and profibrinolytic properties.4 Due to its action on the coagulation pathway, rhAPC, the active form of drug, exposes treated patients to a serious hemorrhagic risk5–8 and its administration was subject to careful evaluation of the risk-to-benefit ratio. Attempts were made to use protein C zymogen, its “inactive” precursor, endowed with anti-inflammatory activity but devoid of anticoagulant properties. Among its advantages, PC is activated “on demand” in sites of major thrombin formation, and this is expected to limit or eliminate unwanted bleeding.

Few case series have been published on adult septic patients receiving protein C zymogen. We hereby describe the largest case series of adult patients with severe sepsis or septic shock receiving PC in a single center.

Patients and methods, setting and study population

After ethical committee approval and with patients’ written consent, we collected data from 23 adult patients with severe sepsis or septic shock admitted to two intensive care units (ICU) of San Raffaele Scientific Institute over a 2-year period. Eleven of these 23 patients were already reported in other publications.9,10 Inclusion criteria were represented by age >18 years, diagnosis of severe sepsis (acute organ dysfunction secondary to documented or suspected infection) or septic shock (severe sepsis plus hypotension not reversed with fluid resuscitation) and two or more organ failures due to sepsis of recent onset (less than 48h); contraindication to receive rhAPC (recent major surgery in most patients); being admitted in the ICU. Exclusion criteria were represented by known allergy to the study product and inclusion in other studies.

In addition to current standard-of-care therapies for severe sepsis and septic shock, patients received PC concentrates (Ceprotin®, Baxter, Wien) administered as a starting bolus (50IU/kg) plus a 3IU/kg/h continuous infusion over 72h.

We measured plasma PC activity, prothrombin time (PT), activated partial thromboplastin time (aPTT), Platelets (PLTs), C-reactive protein (CRP), white cell count (WBC), D-dimer and fibrinogen (FG) values at baseline, at 6 and 12h after PC concentrate administration, then every 12h for 60h. The sequential organ assessment failure (SOFA) score, the Acute Physiology and Chronic Health Evaluation (APACHE II) score, and the simplified acute physiology score (SAPS II) were recorded at baseline (when patient received PC zymogen), daily for 7 days.

Laboratory methods

Serial venous samples (4.5ml) were collected in siliconized Vacutainer tubes (Becton-Dickinson, Plymouth, UK) containing (0.5ml) tri-sodium citrate (0.129M) and in tubes containing 0.5ml of a mixture of tri-sodium citrate and benzamidine–HCl (200mM) at the following times: before the bolus dose, 6h after bolus and every 12h thereafter up to 72h. Within 1h from collection, platelet poor plasma was obtained by centrifugation for 10min at 2000×g at room temperature. PT (Hemoliance Recombiplastin, Instrumentation Laboratory, Lexington, MA), aPTT (STA aPTT Kaolin, Diagnostica Stago, Asnier sur Seine, France), FG (clotting assay, STA Fibrinogen, Stago), and D-dimer (STA Liatest D-D, Stago) determinations were performed on fresh citrated plasma samples with an automated coagulometer (STA, Stago). Plasma aliquots were snap-frozen with methanol and dry ice and stored at −70°C for additional measurements in citrated plasma of PC anticoagulant activity (STA Protein C, Stago), and antithrombin (amidolytic activity, STA Antithrombin, Stago). Blood samples collected in tri-sodium citrate and benzamidine–HCl were also centrifuged as described above with plasma aliquots snap-frozen and stored at −70°C. Within one month, prothrombin fragment 1+2 (F1+2, Enzygnost F1+2, Dade-Behring, Marburg) and thrombin-antithrombin III complex (TAT Enzygnost TAT micro, Dade-Behring, Marburg) were measured with commercially available ELISA kits.

Statistics

Collected data were analyzed through repeated measure ANOVA, chi-square (χ2), and Friedman's test using SPSS® 13 statistical package (Chicago, Illinois). The Z-test for two proportions was employed to compare expected versus observed mortality. A p-value <0.05 was considered statistically significant.

Results

We enrolled 23 consecutive patients with severe sepsis or septic shock. Twenty-one (91%) of them were surgical patients (18 cardiac surgery and one each for thoracic, vascular, urologic and abdominal surgery) and 1 patient presented to the emergency department with septic shock. Mean patient age was 63±12 years (range 25–77) and 4 (17%) were female.

All patients showed signs of sepsis-induced multiorgan dysfunction syndrome: 22 patients had respiratory failure, 16 had acute renal failure requiring renal replacement therapy and 16 had pharmacological sedation. The average APACHE II was 25±5, mean SAPS II was 58±14, and mean SOFA score was 14±2. The timing from surgery (or ICU admission) to the first cultural sample was 5±4.7 days while the timing from surgery (or ICU admission) to PC administration was 7±5.1 days. Seventeen patients had single or multiple cultural examination (in 4 patients the germs were identified in multiple sites and in 6 patients more than one germ was identified). Blood culture (8 patients), bronchoalveolar lavage (10 patients) and urine culture (2 patients) were positive for the following germs: Staphylococcus spp. (7 patients), Escherichia coli (6 patients), Acinetobacter spp. (2 patients), Proteus, Serratia marcescens, Streptococcus spp., Enterobacter cloacae, Klebsiella pneumonia, Citrobacter and Pseudomonas aeruginosa.

Baseline plasma PC activity was 33±18% [normal values 65–140%], and increased to 66±22% at 6h after PC bolus (p<0.001). Afterwards, it remained constantly within normal range values during PC concentrate continuous infusion and was 90±25% at 72h (p<0.001 to baseline) (Fig. 1).

Fig. 1.
(0,07MB).

Trend of protein C zymogen during the 72h of administration.

Changes in laboratory variables after protein C concentrate administration showed in Table 1. A significantly increasing of ATIII values from 49±15 to 81±19 was observed at 60h (p=0.04), FG and fibrin D-dimer showed a trend toward reduction and PLT count tended to increase from 130 (×109/l)±121 (×109/l) to 120 (×109/l)±140 (×109/l) during the 60h period.

Table 1.

Changes in laboratory variables throughout protein C concentrate administration.

  Before bolus  After 61224364860p value 
aPTT (ratio)  40±15.0  41±17.9  40±19.4  40±20.3  38±14.4  36±12.0  33±10.9  0.33 
ATIII  49±14.9  66±19.2  66±26.5  56±21.2  67±23.2  72±13.5  81±18.7  0.04 
D-dimer (mg/ml)  6.0±5.73  5.6±5.92  5.0±6.19  6.2±6.38  4.4±2.90  6.1±1.47  5.2±2.37  0.46 
FG (mg/dl)  550±163.7  526±204.6  626±209.2  672±116.1  717±120.7  674±137.0  654±134.0  0.62 
INR  1.5±0.6  1.5±0.6  1.5±0.7  1.4±0.4  1.3±0.3  1.3±0.3  1.2±0.2  0.08 
PCR (ng/ml)  204±130.1  171±85.7  157±68.3  132±90.7  112±59.5  67±64.4  59±63.0  <0.001 
Platelet count (×109/l)  130±121  110±85  120±120  130±123  140±124  130±137  120±140  0.86 
WBC counts (×109/l)  19±11.1  21±14.7  20±11.3  22±12.3  22±17.5  23±19.5  23±21.6  0.97 

On the inflammatory viewpoint PCR values significantly decreased from 204±130.1 to 59±63.0 during 60h (p<0.01).

We observed a rapid reduction of the SOFA (from 14±2 to 7±4, p<0.001) (Fig. 2), the SAPS II (from 58±14 to 37±12, p<0.001), and the APACHE II (from 25±5 to 14±6, p<0.001) scores at 7 days.

Fig. 2.
(0,07MB).

Variation of Sequential Organ Failure Assessment (SOFA), score during and after protein C zymogen administration.

Septic shock mortality rates in the literature approach 60% and the expected mortality in our sample population was 53±17%. The Z-test for two proportions evidenced a significant reduction between the expected mortality (53%) and the observed mortality 30% (Z value=1.99, p=0.046). In fact, 7 patients of our sample died (30%), all of them by refractory shock. A post hoc analysis showed that the best results in terms of crude mortality were observed in the subgroup of 11 patients with a cardiac index ≥2.5L/min/m2. In that group, only 1 patient (9%) died (Z value=3.5, p=0.001).

We observed two cases of hemorrhagic cystitis, respectively three days and two weeks after PC concentrate interruption. One case of bilateral jugular vein thrombosis was recorded as well. These phenomena could not be attributed to the drug administration. No bleeding complication was reported.

Discussion

To the best of our knowledge this is the largest case series ever reported on the use of PC zymogen. In this study we showed a favorable effects on coagulation, multiorgan function and survival in patients that received PC zymogen.

PC levels increased from 33±18% to 66±22% [normal values 65–140%], at 6h after PC bolus (p<0.001), and kept on increasing during the 72h of administration (p<0.001 to baseline). Interestingly, all our patients had low baseline levels of PC. This finding is important because a low PC value is a strong predictor of unfavorable outcome11–14 and septic patients are associated with increased morbidity and mortality. Despite this baseline data we achieved a survival rate of 70%. Given the expected poor outcome on the basis of the score risks and our patients’ PC activity, the 70% survival rate may indicate that perhaps a beneficial drug effect on survival is present.

In our patients PC levels increased at 6h after PC bolus and remained constant thereafter, furthermore ATIII levels significantly increased after drug administration.

We also reported clinical benefit as documented by the significant reduction in the indices of organ dysfunction (the SOFA). Finally patient mortality was 30% versus the expected 53% and this difference was even more evident if only septic patients with cardiac index ≥2.5L/min/m2 were considered (mortality was 9%).

Consistently with the findings of the largest adult case series (20 patients) published so far15 we achieved normalization of coagulation parameters as a increasing of ATIII, as indicated by prompt raise of plasma PC activity within normal values, and a decreasing of PCR levels; an improvement of indices of organ dysfunction and a beneficial effect on patient survival. Similar findings were noted in our previously published case series that included 9 of these 23 patients.9 A recent systematic review on all the published case reports and case series of adult septic patients receiving PC suggested that mortality rates are low when receiving this drug.10

One interesting finding of our case series is that the beneficial effects on survival were more important in the patients with high cardiac output. The results of our study are important especially in view of the paucity of drugs, techniques or strategies that might reduce perioperative mortality in critically ill patients.16

Limitations

Although this is the largest case series of adult patients receiving PC ever published in literature, the small sample size and the non randomized study design do not allow us to draw definitive conclusions on the beneficial effect of PC administration in severe sepsis or septic shock. Furthermore, we measured only PCR and not other inflammatory markers such as procalcitonin or interleukine-6. On top of this, we acknowledge that the diagnosis of sepsis after major surgery might be challenging and that SIRS without infection is to be taken into consideration. Lastly, in half of our patients sepsis was diagnosed in patients with ongoing LCOS, a condition that is frequent after cardiac surgery and that can further confound the clinical picture of these patients.

Conclusions

The favorable effects on coagulation, multiorgan function and survival suggest potential beneficial effects of PC concentrate on restoring homeostasis, at least as coagulation is concerned, and should raise interest in confirming our and others’ promising results through a randomized clinical trial or at least case match studies.

Conflict of interest

The authors declare no conflicts of interest.

References
[1]
G.S. Martin, D.M. Mannino, S. Eaton, M. Moss
The epidemiology of sepsis in the United States from 1979 through 2000
N Engl J Med, 348 (2003), pp. 1546-1554 http://dx.doi.org/10.1056/NEJMoa022139
[2]
D.C. Angus, W.T. Linde-Zwirble, J. Lidicker, G. Clermont, J. Carcillo, M.R. Pinsky
Epidemiology of severe sepsis in the United States: analysis of incidence, outcome and associated costs of care
Crit Care Med, 29 (2001), pp. 1303-1310
[3]
For the PROWESS-SHOCK Study Group
Drotrecogin alfa (activated) in adults with septic shock
N Engl J Med, 366 (2012), pp. 2055-2064 http://dx.doi.org/10.1056/NEJMoa1202290
[4]
C.T. Esmon
The protein C anticoagulant pathway
Arterioscler Thromb, 12 (1992), pp. 135-145
[5]
For the Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis (PROWESS) Study Group
Efficacy and safety of recombinant human activated protein C for severe sepsis
New Eng J Med, 344 (2001), pp. 699-709 http://dx.doi.org/10.1056/NEJM200103083441001
[6]
E. Abraham, P.F. Laterre, R. Garg, H. Levy, D. Talwar, B.L. Trzaskoma
Drotrecogin alfa (activated) for adults with severe sepsis and low risk of death
N Engl J Med, 353 (2005), pp. 1332-1341 http://dx.doi.org/10.1056/NEJMoa050935
[7]
J.L. Vincent, G.R. Bernard, R. Beale, C. Doig, C. Putensen, J.F. Dhainaut
Drotrecogin alfa (activated) treatment in severe sepsis from the global-label trial ENHANCE: further evidence for survival and safety and implication for early treatment
Crit Care Med, 33 (2005), pp. 2266-2277
[8]
S. Kanji, M.M. Perreault, C. Chant, D. Williamson, L. Burry
Evaluation the use of drotrecogin alfa activated in adult severe sepsis: a Canadian multicenter observational study
Intensive Care Med, 33 (2007), pp. 517-523 http://dx.doi.org/10.1007/s00134-007-0555-9
[9]
M. Crivellari, P. Della Valle, G. Landoni, F. Pappalardo, C. Gerli, E. Bignami
Human protein C zymogen concentrate in patients with severe sepsis and multiple organ failure after adult cardiac surgery
Intensive Care Med, 35 (2009), pp. 1959-1963 http://dx.doi.org/10.1007/s00134-009-1584-3
[10]
G. Landoni, M. Crivellari, G. Monti, C. Gerli, P. Silvani, A. Zangrillo
Human in protein C concentrates in adult septic patient
Signa Vitae, 3 (2008), pp. 13-17
[11]
K. Fijnvandraat, B. Derkx, M. Peters, R. Bijlmer, A. Sturk, M.H. Prins
Coagulation activation and tissue necrosis in meningococcal septic shock: severely reduced protein C levels predict a high mortality
Thromb Haemost, 73 (1995), pp. 15-20
[12]
J.F. Dhainaut, S.B. Yan, Y.E. Claessens
Protein C/activated protein C pathway: overview of clinical trial results in severe sepsis
Crit Care Med, 32 (2004), pp. S194-S201
[13]
C.J. Fisher Jr., S.B. Yan
Protein C levels as prognostic indicator of outcome in sepsis and related diseases
Crit Care Med, 28 (2000), pp. S49-S56
[14]
W.L. Macias, D.R. Nelson
Severe protein C deficiency predicts early death in severe sepsis
Crit Care Med, 32 (2004), pp. S223-S228
[15]
F. Baratto, F. Michielan, M. Meroni, A. Dal Palù, A. Boscolo, C. Ori
Protein C concentrate to restore physiological values in adult septic patients
Intensive Care Med, 34 (2008), pp. 1707-1712 http://dx.doi.org/10.1007/s00134-008-1140-6
[16]
G. Landoni, J.G. Augoustides, F. Guarracino, F. Santini, M. Ponschab, D. Pasero
Mortality reduction in cardiac anesthesia and intensive care: results of the first International Consensus Conference
HSR Proc Intensive Care Cardiovasc Anesth, 3 (2011), pp. 9-19
Copyright © 2012. Elsevier España, S.L. and SEMICYUC
Idiomas
Medicina Intensiva

Suscríbase al Newsletter

Opciones de artículo
Herramientas
es en
Política de cookies Cookies policy
Utilizamos cookies propias y de terceros para mejorar nuestros servicios y mostrarle publicidad relacionada con sus preferencias mediante el análisis de sus hábitos de navegación. Si continua navegando, consideramos que acepta su uso. Puede cambiar la configuración u obtener más información aquí. To improve our services and products, we use "cookies" (own or third parties authorized) to show advertising related to client preferences through the analyses of navigation customer behavior. Continuing navigation will be considered as acceptance of this use. You can change the settings or obtain more information by clicking here.
es en

¿Es usted profesional sanitario apto para prescribir o dispensar medicamentos?

Are you a health professional able to prescribe or dispense drugs?