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1094 PART 10: The Surgical Patient

TABLE 115-4 Postoperative Management of Lung Transplant Recipient TABLE 115-6 Risk Factors independently Associated With Primary Graft
Ventilation Lung-protective ventilation: Dysfunction
6 cc/kg, plateau pressures <30 mm Hg Donor Risk Factors Recipient Risk Factors
Minimization of high airway pressures Donor age >45 Recipient BMI >25
Fluid Judicious fluid administration Head trauma Recipient female sex
Attempt to achieve dry weight without compromising EuroCollins preservation solution Recipient diagnosis: primary or
end-organ function Single lung transplant secondary pulmonary fibrosis
Immunosuppressive medications Maintenance: triple drug therapy with a calcineurin Increased ischemic time
inhibitor, an antimetabolite, and a corticosteroid; avoid a
mTOR inhibitors in early posttransplant phase (risk of Elevated recipient PAP at time of transplant
airway dehiscence) a PAP, pulmonary artery pressure 6
Induction: some centers adopted use of polyclonal Boffini et al. 28
antibodies
Antimicrobial prophylaxis See section Infectious Complications PGD is responsible for approximately 30% of early mortality postlung
Antimicrobial prophylaxis in CF See section Infectious Complications transplant (30 day) and is one of the greatest risk factors associated with
a prolonged ICU stay. There are multiple risk factors for PGD. These
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include prolonged ischemic time, speed of reperfusion of the lungs, and
common complications is imperative to enhance long-term outcomes unsuspected donor lung pathology such as aspiration or lung contusions
in this population. Below are the more common complications that can (Table 115-6).
arise posttransplant. Given that PGD is largely transient and reversible, management is
Primary Graft Dysfunction: Primary graft dysfunction (PGD) is one mainly supportive with the implementation of lung-protective ventilator
of the most common complications after lung transplantation. It strategies to minimize secondary injury from ventilator-induced lung
represents a forme fruste of noncardiogenic pulmonary edema and injury. In the case of severe PGD, more advanced and, as yet, unproven
is characterized by progressive lung injury, with both epithelial and treatments are often used to treat hypoxemia.
endothelial damage. PGD can develop as a result of an accumulation Fluids: Maintaining a negative fluid balance with diuresis, but without
of insults on the lungs from donor management/ventilation, retrieval, compromising end-organ function may help minimize the duration
storage, and implantation of the lungs. PGD typically occurs in the of PGD given the new lungs’ impaired ability to mobilize pulmonary
first few hours to 72 hours posttransplantation. PGD needs to be dif- edema. Whether the use of colloidal solutions or albumin offers an
ferentiated from other etiologies of poor gas exchange in the imme- advantage in this situation has not been systematically evaluated.
diate posttransplant period (see Table 115-6). The ISHLT Working
Group on PGD developed a standardized definition of PGD based Inhaled nitric oxide (iNO): In severe PGD, the role of iNO has been
(P/F) ratio and chest infiltrates (see Table 115-5). It is a controversial with much of its support being extrapolated from ARDS
on Pa O 2 /Fi O 2 studies. Similar to ARDS, it has been shown to improve oxygenation
spectrum of injury that occurs to some degree in most patients but
manifests clinically in 10% to 20% of patients. At its worst, it can through enhancing ventilation/perfusion matching; however, this
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48
progress to severe ARDS requiring maximum ventilatory support, has not translated to an impact on mortality. While a randomized
and in some cases severely impairing pulmonary artery pressures due controlled trial showing survival benefit is lacking, a trial of iNO may
to refractory hypoxia necessitating inhaled NO, intravenous epopro- be justified in select cases of severe hypoxemia or elevated pulmonary
stenol, or even ECLS. In less severe cases, it may resolve within 24 to artery pressures. Although early preclinical and clinical evaluations
48 hours. The severity of PGD has been linked to both ICU outcomes suggested benefit in preventing PGD, an RCT did not show any ben-
and long-term graft function. 47,48 efit of iNO relative to placebo gas in reducing either the incidence or
severity of PGD. 49
Prostaglandin E1 (PGE1): In experimental models, the use of a PGE1
TABLE 115-5 Primary Graft Dysfunction has been shown to ameliorate reperfusion injury and has the poten-
1) Presence of diffuse pulmonary infiltrates involving the lung allografts on postoperative tial to be a promising option. It is often implemented in severe PGD
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chest x-ray refractory to mechanical ventilation and iNO. However, owing to
2) Pulmonary arterial oxygen and fraction of inspired oxygen ratios (P/F ratio) in mm Hg its nonselective vasodilation it has the potential to contribute to both
a. Grade 1 PGD (PF ratio >300) systemic hypotension and/or deterioration in ventilation/perfusion
b. Grade 2 PGD (PF ratio 200-300) matching in the lung.
c. Grade 3 PGD (PF ratio <200) Extracorporeal life support (ECLS): Occasionally patients with severe
3) No other secondary cause of graft dysfunction readily identified such as: PGD will be refractory to mechanical ventilation, iNO, and PGE1.
a. Cardiogenic pulmonary edema: defined as prior evidence of LV systolic function on ECLS has promise as a lifesaving alternative at this stage. Early initia-
preoperative echocardiogram or postoperative echocardiogram and resolution of tion of ECLS (in the OR or within 24 hours) has led to survival rates
infiltrates with effective diuresis of 50% to 80%. The evaluation of the Extracorporeal Life Support
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b. Pathologic evidence of rejection Organization (ELSO) registry of any patients receiving ECLS posttrans-
c. Pneumonia (evidence of presence of fever, leukocytosis, purulent secretions, and plant report hospital survival rates of 42%. However, the effect of early
51
positive culture on bronchoscopy) ECLS on intermediate and long-term outcomes has not been systemati-
d. Pulmonary venous outflow obstruction as demonstrated on TEE, surgical cally evaluated. Uniform criteria on when to initiate ECLS are needed.
reexploration, or postmortem examination Improved experience in ECLS, better patient selection and timing, and
4) All patients on oxygen via nasal cannula with fraction of inspired oxygen estimated as refinements in technology have the potential to have a great impact
less than 0.3 will be graded as 0 or 1 based on CXR on future outcomes of patients with PGD. Currently, an international
5) All subjects on extracorporeal life support are graded as grade 3 multicenter trial is underway evaluating the use of ECLS for acute respi-
Data from Christie J, Carby M, Bag R, et al. Report of the ISHLT Working Group on primary lung graft ratory distress syndrome. While not directly related to primary graft
dysfunction part II: definition. A consensus statement of the International Society for Heart and Lung dysfunction, given the similarities between the two entities, the results
Transplantation. J Heart Lung Transplant. 2005;24(10):1454-1459. may help develop more concrete indications for initiation.

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