Reperfusion Syndrome and Vasoplegic Syndrome in Liver Transplant Surgery
Condition: Postperfusion Syndrome
MeSH terms: Vasoplegia; Syndrome
Study type: Observational

Summary: 
      The incidence of postreperfusion syndrome (PRS) and vasoplegic syndrome (VS) is unknown, and
      occasionally can be confused since these syndromes share some hemodynamic characteristics. In
      these cases, monitoring with Swan Ganz catheter may be useful to make the differential
      diagnosis. The main outcome was to analyze reperfusion syndrome and vasoplegic syndrome in
      patients receiving vasoactive support during liver transplant surgery, in terms of incidence,
      risk factors and postoperative complications.
    

Detailed description: 
      Introduction:

      At the time of the liver reperfusion, many inflammatory mediators coming from the liver graft
      to the systemic circulation produce a sudden load of cold and acidotic blood. At this stage
      of graft revascularization, it has been seen an increase of pulmonary vascular resistance
      index (PVRI) and pulmonary arterial pressure (PAP) and a reduction in systemic vascular
      resistance index (SVR), heart rate (HR), cardiac index (CI) and arterial blood pressure
      (ABP).

      In this context, some patients suffer postreperfusion syndrome (PRS). This syndrome was first
      defined by Aggarwal et al as a decrease in the MAP greater than 30% of at least one minute
      duration and during the five minutes following the portal unclamping and was associated with
      several preoperative risk factors and postoperative complications. The variety of the risk
      factors presented in previous studies suggest that the PRS occurs in an unpredictable manner.
      These risk factors were described related to the organ of the donor; related to the recipient
      of the liver graft, and related to the surgical technique. The incidence varies largely among
      the considered studies, ranging from 12% to 77% and it can respond not only to preoperative
      and intraoperative factors associated with anesthetic-surgical practice, but also to the
      different criteria for definition of PRS as well as to the administration of vasoactive drugs
      to prevent or treat it.

      On the other hand, the incidence of vasoplegic syndrome (VS) is not described and could be
      confused with PRS We studied the patients who received vasoactive support during liver
      transplant surgery and presented PRS considering the Aggarwal et al. definition, and VS
      considering the Ozal et al. criteria.

      Methods:

      Design: Retrospective observational study. Inclusion criteria: Patients undergoing liver
      transplantation who received vasoactive support and monitored with Swan Ganz catheter
      Exclusion criteria: liver transplantation for acute liver failure, combined liver and kidney
      transplantation, renal dysfunction (glomerular filtration <60), moderate/severe vascular and
      valvular heart disease, moderate/severe hepatopulmonary syndrome, moderate/severe
      portopulmonary syndrome, and re-transplantation

        -  Study outcomes The primary objective of our study was to determine the incidence and
           risk factors of PRS and VS in norepinephrine/adrenaline patients according to the
           Aggarwal and Ozal criteria respectively. The second objective is to determine the
           postoperative complications.

        -  Data collection Preoperative variables related to recipient and donor were analyzed.
           Intraoperative variables were recorded at each stage of the surgery: pulmonary capillary
           wedge pressure (PCWP), mean pulmonary arterial pressure (mPAP), MAP, heart rate (HR),
           cardiac index (CI), systemic vascular resistance index (SVRI), central venous pressure
           (CVP), bleeding, need for transfusions, doses of vasoconstrictors, global requirements
           for bicarbonate and calcium chloride, presence of malignant arrhythmias (fibrilation,
           flutter, ventricular tachycardia) or ischemic electrocardiographic abnormalities. The
           times of each surgical phase, duration of cold ischemia and the weights of the liver
           (donor/recipient) were recorded too. Postoperative data collected included: graft
           rejection, a second surgery after liver transplant, the need for re-transplantation,
           renal dysfunction (glomerular filtration <60), hospital stay, days of hospitalization
           and survival.

      All items that could be used to identify the patient (clinical record ID number or name) were
      removed to protect personal data.

      -Measurement of hemodynamic data The hemodynamic parameters (MAP, HR, SVR, CVP, CI, PCWP and
      mPAP) of each stage of the liver transplant surgery (dissection phase, anhepatic phase prior
      to unclamping of the IVC, at 1 and 5 min after graft reperfusion, and in the neohepatic phase
      after completion of the vascular anastomosis) were collected.

      The PRS criteria were decrease in the mean arterial pressure ≥ 30% mmHg during the first 5
      minutes after unclamping of the IPV, decrease in CI and SVR respect to baseline (anhepatic
      phase), and increase of the PCWP, CVP and mPAP respect to baseline.

      Association between PRS and preoperative, intraoperative, and postoperative variables were
      analyzed and compared between the two groups (for PRS + and PRS - groups).
    

Intervention name(s): noradrenaline/adrenaline
Intervention type(s): Drug
Intervention description(s): norepinephrine adrenaline in patients with Swan-Ganz catheter monitoring during liver transplantation
Other intervention name(s): Swan-Ganz catheter monitoring
Intervention MeSH terms: Epinephrine; Racepinephrine; Norepinephrine; Epinephryl borate
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        Consecutive patients ≥ 18 years-old, who underwent liver transplant surgery, monitored with
        Swan-Ganz catheter, with norepinephrine/adrenaline support during transplant surgery
      
Keywords: postreperfusion syndrome; vasoplegic syndrome