Jacek Prokopowicz, Lidia Nowicka, Krzysztof Guz, Tadeusz M. Orłowski, Dariusz Dziedzic
Pneumonectomy in the heart transplanted patient. A case report
Department of Anaesthesiology,
Head: J. Prokopowicz, M.D. Dept of Surgery,
Head: prof. T. Orłowski, Institute for Tuberculosis and Pulmonary Diseases, Warsaw, Poland
54-yr-old male heart-transplanted patient with chronic renal failure was scheduled for a right-side pneumonectomy due to the bronchial cancer. He was anaesthetized with a propofol target control infusion (TCI) and a high thoracic epidural block. During the procedure special attention was paid to the adequate fluid loading and renal function. Surgery and postoperative period went uneventful and patient was discharged nine days later.
Organ transplanting, for many years, has ceased to be a clinical experiment and their number increases each year with the progress in immunosuppression. Despite successful transplanting, these patients are always considered as persons of the increased risk, not necessarily involving the transplanted organ . The case described below presents the preoperative problems related to pneumonectomy in a patient after heart transplantation.
A 54-year old male was admitted to the Thoracic Surgery Department with a diagnosis of planoepithelial carcinoma of the right lung (T2N0M1). The diagnosis was made in December 1998 after routine chest X-ray and confirmed by bronchoscopy and CT-scan. Nine months earlier the patient underwent a heart transplant for congestive cardiomyopathy. In 1993, because of arteriosclerosis, his left lower limb was amputated. At the time of admission he was treated for renal insufficiency with hyperkalemia (urea plasma level 105 mg/dl; creatinine-2.9 mg/dl; potassium- 6.5 mmol/l).
On clinical examination the signs of malnutrition were noted - BMI 17.2 kg/m2 (55 kg/178cm). The liver was palpable 3cm below the costal margin. Preoperative tests did not reveal any signs of transplanted heart failure, or transplant rejection.
The patient was scheduled for surgery, despite the limited respiratory reserve: FEV1- 53%; FEVC- 71% normal. It was accepted that the abnormal spirometry resulted from the exclusion of a part of lung parenchyma. General condition of the patient justified the surgery, as the physical effort tolerance seemed satisfactory. This was, however, difficult to document by objective tests, as the patient leg was amputated.
The surgical procedure was carried out under total intravenous anaesthesia combined with thoracic epidural analgesia. One hour before the operation the patient received orally midazolam 7.5 mg as premedication. Before induction of anaesthesia an 18G epidural catheter (Perifix, B.Braun, Germany) was inserted at the vertebrtal interspace Th4-Th5. The catheter was introduced from the median approach and advanced 4cm in the cranial direction. A mixture composed of 0.5% bupivacaine 2ml, fentanyl 0.1 mg (Polfa, Poland) and 2 ml of 0.9% NaCl was injected to the epidural space. This produced analgesia from Th3 to Th8 spinal segments. After the stabilisation of the analgesia level, the patient was anaesthetised with etomidate, fentanyl and pancuronium) and intubated with a bronchial double lumen tube for lung separation.
Invasive blood pressure (IBP) and central venous pressure (CVP) were monitored. Propofol in a Target Controlled Infusion (TCI) was the main agent of total intravenous anaesthesia. For this purpose the Graseby 3500 Diprifusor pump (Graseby, Great Britain) was used. The initial Target Plasma Concentration (TPC) was set at 1.0 mg/ml, and the dose was infused during 3 minutes. The depth of anaesthesia was modified, depending on the phase of the procedure, in the range of concentration 0.8-1.5 mg/ml (2.5-4 mg/kg/h). Epidural analgesia was continued during surgery. 0.5% bupivacaine 2 ml and fentanyl 0.1 mg were injected in hourly intervals (4 doses in total). During the procedure (3h 20 min) the patient did not require additional intravenous doses of fentanyl or rocuronium. Blood pressure (before induction 144/78 mm Hg - 19.2/10.4 kPa) during anaesthesia remained in the range 110-160/70-100 mm Hg (14.7-21.3/9.3-13.3 kPa). A short lasting, (few minutes), episode of hypotension to 80/50 mm Hg (10.7/6.7 kPa) caused by bleeding during preparing the lung, was corrected by rapid infusion of crystalloid solution. The baseline CVP value in the patient placed in prone position equalled 7 mm Hg (0.93 kPa) and raised to 12-15 mm Hg (1.6- 2.0 kPa) after changing the position to the lateral one. This was one of the parameters regulating the volume and the rate of intravenous infusion of fluids. The venous pressure readings were influenced by surgical manoeuvres inside the thoracic cavity. Throughout the procedure the patient was receiving a continuous intravenous infusion of dopamine at a dose of 3 mg/kg/min, to protect the renal function. At the end of surgery (beginning of skin suture) the infusion of propofol was stopped and atropine with neostigmine was administered. The patient was extubated in the operating theatre 8 minutes after the end of surgery, and was transferred to the Intensive Care Unit.
In the postoperative period the treatment concentrated on:
- infection prophylactics (antibiotic treatment maintained until the removal of drains);
- continuation of immunosuppression (cortisosteroid therapy during the first 2 postoperative days, then return to the preoperative scheme, under serum cyclosporine concentration monitoring);
- forced diuresis (minimally 100 ml/h) using loop diuretics and a low-dose dopamine infusion, which enabled the maintenance of biochemical renal function parameters at a level slightly below the preoperative values;
- continuous epidural analgesia (up to the third postoperative day) making possible the elimination of parenteral administration of opioids and early postoperative physiotherapy.
No complications were observed in the postoperative period. Five days after surgery the patient was transferred from the ICU to the thoracic surgery ward and was discharged home on the ninth day after the operation in good general condition.
The decision-making process in the choice of anaesthetic technique and perioperative treatment had to involve the pathophysiology of 3 body systems :
circulatory: in the aspect of the dennervated heart and generalised arteriosclerosis. Additionally, as the result of pneumonectomy, the vascular bed capacity is further reduced, which may cause a marked increase in pulmonary vascular resistance and afterload to the right ventricle;
respiratory: pneumonectomy in the patient with borderline functional respiratory parameters and increased susceptibility to infection (immunosuppressive treatment after heart transplant);
urinary: maintenance of renal function, being already insufficient (with hyperkalemia).
The method of anaesthesia was chosen to minimalise cardiodepressive action of the drugs used, as well as the dependence of their effects on renal metabolism .
Segmental epidural analgesia at the thoracic level carries lesser risk of cardiovascular instability, than at the lumbar levels. This is a consequence of the fact, that the thoracic venous vascular bed plays mainly the role in blood return to the heart and is not able to sequestrate as much blood volume, as splanchnic or musculocutaneous vascular bed. That is why in epidural analgesia limited to Th4-Th8 levels the required supplementation of circulating blood volume is smaller than in abdominal or lumbar analgesia. The possible cardio-depressive action of thoracic epidural analgesia (TEA), resulting from the autonomic nervous blockade of the heart, is not relevant in patients after heart transplant, as the extrinsic innervation of the transplanted organ does not exist . At the same time, efficient regional analgesia enables to limit general anaesthesia to the maintenance of unconsciousness and muscle relaxation needed for artificial ventilation. That is why TCI of propofol with a microprocessor-steered pump was chosen. In the described case, only very low concentrations of propofol (0.8-1.5 mg/ml) were sufficient to maintain anaesthesia. This could have been attributed to the high susceptibility of the patient to midazolam, given as premedication, as well as the efficient TEA action. The most important arguments in choosing propofol were its neutral influence on renal function and no reported interaction with immunosuppresive drugs .
As a dennervated heart is refractory to the drugs influencing the autonomic nervous system, the meticulous intraoperative control of fluid balance is necessary, to avoid hypo- or hypervolaemia. This was important for assessment of vascular bed filling, "loading" of the healthy lung and renal function control.
Maintaining and protecting renal function required an increased volume of intravenous fluid transfusion and forcing diuresis by loop diuretic agents, dopamine infusion (3mg/kg/min) and avoiding hypotension. During the first 3 postoperative days circulatory parameters, urine output and fluid balance were strictly observed to maintain effective renal filtration. The water balance was maintained close to zero, in order to avoid fluid retention in the remaining lung.
The need for immunosuppression, mandatory after organ allotransplantation, was an indication to perioperative parenteral corticosteroid administration and the early enteral feeding. This enabled the early return to the preoperative scheme of the immunosuppressive therapy and adequate nutrition. In the postoperative period, the difficulty to predict bioavailability of orally administered cyclosporine, required the adjustment of this drug doses to its serum concentration.
The necessity of the fastest possible rehabilitation of the patient is accepted as a rule. Physiotherapy should be started at the day of surgery and the thoracic drainage removed as early, as possible to minimalise the risk of infection in the immuno-compromised patient. Epidural analgesia played a significant role, alleviating pain following thoracotomy.
Originally published in Anestezjologia Intensywna Terapia 31; (4), 251-253, 1999.
1. Bailey P., Stanley T.: Anesthesia for patients with a proior cardiac transplant. Journal of Cardiothoracic Anesthesia 1990, 4, 38-47.
2. Shaw I., Kire A., Conacher I.: Anesthesia for patients with transplanted hearts and lungs undergoing non-cardiac-surgery. British Journal of Anesthesiology 1991, 67, 772-778.
3. Payne N.: Anesthetic implications of immunosuppressants used for transplantation. International Anesthesiology Clinics 1995, 2, 93-106.
4. Stover E., Siegel.: Physiology of the transplanted heart. International Anesthesiology Clinics 1995, 2, 11-20.
5. Sharpe M.: Anesthesia and the transplanted patient. Canadian Journal of Anesthesiology 1996, 5, 889-893.