Anaesthetic considerations in chronic renal failure

Preoperative Haemoglobin Levels

It is a common practice in many anaesthetic centres throughout the world to require a minimum preoperative haemoglobin level of 10g/100 ml of blood or more, but very few references are quoted by writers on this subject. A search of relevant medical literature has been made in an attempt to establish the origin and significance of the preoperative haemoglobin requirements recommended.

Anesthesia and ventilation for the uremic child

This article reviews the management of the uremic child from the perspective of an anesthesiologist and cardiopulmonary clinician. The acute stresses of anesthesia, surgery, and mechanical ventilation mandate a systematic, functional approach to addressing rapidly progressing complications that may occur in these patients. Chronic renal failure may be the result of many different renal diseases, but most share common implications during anesthesia. Furthermore, anesthesia can be associated with acutely decreased function of both normal and diseased kidneys.

Anaesthesiological complications in renal transplantation: a retrospective study of 500 transplantations

This retrospective study consisted of 500 consecutive renal transplantations performed between September 1977 and September 1981. Preoperatively, congestive heart failure was registered in 262 cases (53.0%) and blood pressure disease in 352 cases (71.3%). The total number of patients with ischaemic heart disease was 22 (4.5%). General anaesthesia was given in 493 and regional anaesthesia in seven cases. In general anaesthesias, tubocurarine was the main relaxant and halothane the main inhalation agent used. Major complications during anaesthesia were blood pressure changes with a higher incidence of hypotension (49.6%) than hypertension (26.8%). Severe cardiac arrhythmias were rare and no intraoperative deaths occurred. One patient was successfully resuscitated in the ICU postoperatively, this being possibly related to hypoventilation caused by prolonged muscular relaxation. Other rare complications included one pneumothorax, one haemo- and hydrothorax, and two large haematomas all caused by preoperative central venous cannulation. In 69 cases (14.0%) additional neostigmine doses and in 34 cases (6.9%) naloxone was given at the end of anaesthesia. Pneumonia during the first postoperative week was recorded in 11 cases (2.2%), and occurred only in patients who received general anaesthesia. One of the three patients who died during the first week developed pneumonia postoperatively.

Anaesthesia for renal transplantation--5 years' experience

Two hundred and seventy patients underwent anaesthesia for 280 renal transplants between October 1977 and October 1982. Their medical records were studied retrospectively. These patients were representative of the end-stage chronic renal failure population, with the usual high incidence of cardiovascular and biochemical abnormalities. Most received general anaesthesia, with an intravenous barbiturate, muscle relaxant, narcotic and volatile supplement sequence being the most common. There were no intra-operative deaths. One postoperative death was felt to be influenced by the anaesthetic management. Four patients had life-threatening cardiac complications and a further four required postoperative respiratory support, three for delayed recovery of neuromuscular function and one for "recurarisation". Less serious complications were considerably more common. General anaesthesia utilising suxamethonium and tubocurarine as the relaxants and halothane as the volatile supplement is least likely to result in complications. Changes to this anaesthetic sequence are likely with the introduction of new agents.

Anaesthesia for the patient with impaired renal function

Patients with renal disease are at risk of further deterioration of renal function and acute tubular necrosis when subjected to anaesthesia and surgery. Optimal fluid loading and careful selection of anaesthetic techniques and agents, appropriate monitoring and the use of mannitol and dopamine assist in the maintenance of renal blood flow and help preserve renal function in these patients. In association with renal failure, physiological changes in other systems result in reduced oxygen supply to the tissues, metabolic disturbances, impairment of the coagulation and immune defence mechanisms and an increased risk of cardiac and cerebrovascular catastrophe. Although many anaesthetic techniques including regional analgesia may be used successfully in these patients caution with most drugs, especially pethidine, phenoperidine, suxamethonium and all non-depolarising neuromuscular relaxants is recommended. Of the volatile anaesthetics currently available, halothane is the agent of choice. Oxygen therapy and close monitoring of cardiorespiratory function are necessary postoperatively.

Enflurane anesthesia in living donor renal transplantation

Two groups of patients undergoing elective living donor renal transplantation were studied during enflurane or halothane supplemented anesthesia. The duration of anesthesia was similar in both groups. The mean administered enflurane dose was 243 vol % min; the corresponding halothane dose was 56 vol % min. In the enflurane group, the mean serum inorganic fluoride level peaked at 21.0 mumol/l 3 h after the end of anesthesia. The inorganic fluoride level in urine produced by the renal graft increased continuously, but did not peak, during the first 24 postanesthetic hours. The renal graft quickly started to function in all patients in both groups. The frequency of rejection reactions was higher in the enflurane group than in the halothane group. Serum creatinine levels decreased rapidly in both groups. Urine flow was high on the day of transplantation, but normalized on the first postanesthetic day. Renal sodium clearance decreased earlier in the enflurane group than in the halothane group. This difference was statistically significant on the first postanesthetic day. In the enflurane group, the required pancuronium dose was significantly lower than in the halothane group. In one patient in the enflurane group, the serum inorganic fluoride level increased to 37.5 mumol/l. In this patient renal tubular function may have been affected, but the change was not conclusive since a pronounced rejection of the graft became evident. Since increases in serum inorganic fluoride level approaching 75% of the threshold level for nephrotoxicity in normal kidneys may occur, enflurane should not be routinely used in anesthesia for renal transplantation.

Neurolept anaesthesia for the renal transplant operation

Between October 1973 and December 1976, neurolept anesthesia was used in 176 consecutive renal transplantations carried out in 155 patients. For premedication, the combination either of droperidol, diazepam and atropine or of oxicon and scopolamine was used; the latter was found to be more effective. The induction agent was droperidol or thiomebumal sodium, the barbiturate being found to be preferable. For maintenance, nitrous oxide and fentanyl were employed. Pancuronium was given as a muscle relaxant. The fact that the patients belonged to a high-risk category as regards anesthesia was apparent from the frequent occurrence of abnormal features in the heart-lung radiographs (47%) and ECG (53%). As could be expected in uraemic patients, anaemia and hypertension were fairly common. Induction was followed by a marked fall in blood pressure in 30% of the patients. During anaesthesia, there was a drop in blood pressure of more than 30% of the initial value in 35% of the patients, usually associated with a blood loss. In the majority of cases the course the anaesthesia was uneventful. In four patients (2.3%), the onset of respiration was delayed and re-intubation was resorted to. One patient developed arrhythmia requiring treatment. There was no evidence of nephrotoxicity. The per- and postoperative mortality was nil. The findings in this series indicate that neurolept anaesthesia is suitable for renal transplant operation.

Vascular surgery in an anephric patient

A 33-year-old man with chronic renal failure underwent repair of an expanding aortic aneurysm. The management of the case is described and the anaesthetic problems discussed.