A 50 year old man, who had a heart lung transplant 8 years earlier, presents to your ICU with pneumonia. Discuss the clinical issues specific to the heart lung transplant that will need consideration in your management of this patient.
a) Opportunistic infections - This can result in a wide range of opportunistic organisms causing infection including Pneumocystis, Aspergillus and CMV. It will therefore require early aggressive investigation and broad spectrum bacterial, fungal and possibly viral cover.
b) Immunosuppression : Ongoing immunosuppression will need to be carefully managed in consultation with the transplant unit
c) Cardiac issues- The transplanted heart is denervated. It is only responsive to directly acting drugs/hormones present in the circulation. Normal compensatory cardiac autonomic reflexes are not present and therefore the heart is more sensitive to directly acting drugs and less able to rapidly respond to changes in intravascular volume. This will clearly affect the ability to clinically assess a response to therapy and determine adequacy of therapy.
° Altered ECG /rhytm strip patterns
° Premature diffuse obliterative coronary atherosclerosis which results in impaired ventricular function
d) Respiratory issues - Impaired cough and clearance of secretions.
° Impaired lung function due to Obliterative Bronchiolitis ( a manifestation of chronic rejection)
° Bronchial or tracheal stenosis relating to the original anastomotic site.
e) Renal – altered renal function secondary to immunosuppressive drugs.
f) Altered adrenal function secondary to steroid use, need for steroid cover.
It is difficult to answer such a question intelligently without the experience of having worked in a cardiac transplant unit.
Fortunately, there are good papers.
This question benefits from a structured approach, and the systems-based structure provided by the college is as good as any. I will attempt to reorganise this question into a locally familiar alphabetic algorithm. For a broader overview of complications following heart-lung transplantation, and specifically sepsis in the heart-lung transplant recipient, there are dedicated chapter in the Required Reading section.
Renal and electrolyte abnormalities:
Note how weirdly the range of bugs is arrayed. The community pathogens are fairly bog-standard, but the Stanford people found that gram-negatives dominated the hospital-acquired infectious lung flora.
Immunesuppression in the context of an acute infectious illness may have to be continued, because its cessation may result in catastrophic rejection.
Cisneros, J. M., et al. "Pneumonia after heart transplantation: a multiinstitutional study." Clinical infectious diseases 27.2 (1998): 324-331.
Reichenspurner, Hermann, et al. "Stanford experience with obliterative bronchiolitis after lung and heart-lung transplantation." The Annals of thoracic surgery 62.5 (1996): 1467-1473.
Gao, Shao-Zhou, et al. "Accelerated coronary vascular disease in the heart transplant patient: coronary arteriographic findings." Journal of the American College of Cardiology 12.2 (1988): 334-340.
Yusuf, S. A. L. I. M., et al. "Increased sensitivity of the denervated transplanted human heart to isoprenaline both before and after beta-adrenergic blockade."Circulation 75.4 (1987): 696-704.