ANAESTHESIA IN PATIENTS WITH ABNORMAL HAEMOGLOBIN SYNDROMES: A PRELIMINARY REPORT

Brit. J. Anaesth. (1971), 43, 1159

ANAESTHESIA IN PATIENTS WITH ABNORMAL HAEMOGLOBIN SYNDROMES: A PRELIMINARY REPORT BY

S. A. ODUNTAN AND W. A. ISAACS SUMMARY

There have been very few reports of the effects of anaesthesia in patients with abnormal haemoglobin syndromes (Shapiro and Poe, 1955; Bauer, 1958; Browne, 1965; Gilbertson, 1965; Holzmann et al., 1969); some of the authors have recorded low morbidity and mortality after anaesthesia (Browne, 1965; Holzmann et al., 1969), while others have not (Shapiro and Poe, 1955; Bauer, 1958; Ciliberti et al., 1962; Gilbertson, 1965; Rosenbaum, 1965). However, there seems to be some agreement that the risks of anaesthesia are very high in patients with haemoglobin SS and less so in patients with other haemoglobin combinations such as SC, AS and AC. The purpose of this investigation was twofold: (1) to study the sickling tendencies and blood-gases in patients with abnormal haemoglobin syndromes when subjected to anaesthesia and surgery, and (2) to review the anaesthetic and postoperative records of all such patients who had been subjected to anaesthesia and surgery over the past two years whether or not they were included in the first study, so as to establish the effect of S. A. ODUNTAN, M.B., B.S.(DURH.), D.A.(ENC), F.F.A.R.C.S.I., Department of Anaesthesia; W. A. ISAACS, M.A., B.M., B.CH.(OXON), M.R.C.S., M.I.BIOL.(ENG.), Depart-

ment of Haematology; University College Hospital, Ibadan, Nigeria.

anaesthesia, as administered here, on the manifestations of sickle-cell disease. METHODS

Twenty-four consecutive patients with abnormal haemoglobin syndromes were included in the sickling and blood-gas studies during a 2-year period. An hour after the administration of premedication, the patients were brought into the anaesthetic induction room. With the patient supine and at rest, 3 ml of venous blood was collected from the patient and put in a sequestrene-treated container. After the hand had been warmed for 5 minutes, arterialized capillary blood was collected from the pulp of one of the fingers. The venous blood was sent to the laboratory for sickling studies using the method of Luzzatto, Nwachukwu-Jarrett and Reddy (1970). This consisted of counting the number of initially sickled cells in a blood film made from a drop of the blood on a slide. Thereafter the blood was incubated with sodium metabisulphite in a mixture of glucose and Krebs-Ringer buffer and the number of sickled cells at 15, 30, 45 and 60 minutes counted. For each sickling study, the cells were fixed in 18 per cent formalin for 2 hours, smeared and stained with Leishman; 500

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

Sickling and blood-gas studies were done before, during and after anaesthesia in 24 patients with abnormal haemoglobins (4 SS, 4 SC, 5 AC and 11 AS) who were undergoing surgery. The mean numbers of sickled cells per hour obtained for these abnormal haemoglobin groups were not increased by the effects of anaesthesia. As far as the blood-gas tensions were concerned, the mean Pa02 was much higher during anaesthesia than in the pre- and postanaesthetic periods; whereas the PaC02 and pH were not much altered. In the second part of this study, the anaesthetic and postoperative records of 33 patients with abnormal haemoglobins (5 SS, 5 SC, 5 AC and 18 AS), undergoing 50 surgical procedures were reviewed. There were only two deaths recorded and these were in the AS haemoglobin group. Death was unrelated to the abnormal haemoglobin state in one, while it cannot be entirely excluded in the other. Some recommendations in respect of the anaesthetic management of these patients are proposed.

1160

BRITISH JOURNAL OF ANAESTHESIA

TABLE I

Mean blood-gas tensions in relation to anaesthesia in abnormal haemoglobin syndromes.

SS (4 patients) SC (4 patients) AC (5 patients) AS (10 patients) AS (Fallot's Tetrad) (1 patient)

Pre-operative Paco2 Pao2 (mm (mm Hg) Hg) PH 43.2 85.5 7.392 39.5 76.2 7.357 41.0 80 7.340 36.3 76 7.416 7.30 27 45

Intra-operative Pao2 Paco2 (mm (mm Hg) Hg) pH

Postoperative Pao2 Paco2 (mm (mm pH Hg) Hg)

127 96.7 124.2 115.2 50

101 72 75.6 93.0 41

45.7 30.5 35.0 38.0

7.390 7.462 7.344 7.343

48

7.28

43.2 47.7 39.4 37.7

7.362 7.370 7.336 7.369

42

7.37

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

cells were counted for each estimation and the adults, and atropine alone in children. Induction percentage of sickled cells noted. Measurements of anaesthesia was achieved in children with a of Po2, Pco2 and pH were carried out on the mixture of halothane and oxygen or trichloroethycapillary blood within 10 minutes of collection lene, nitrous oxide, and oxygen, but in adults using Radiometer micro-electrode equipment. sodium thiopentone administered by slow intraOxygen tension was determined polarographically venous injection was preferred. Anaesthesia was using a Clark-type electrode (E5O4O) with poly- maintained with a mixture of nitrous oxide and propylene membrane. Carbon-dioxide tension was oxygen with halothane or trichloroethylene supestimated using a Severinghaus type carbon plementation. Relaxant drugs such as tubodioxide electrode (E5O3O), calibrated with known curarine, gallamine or pancuronium were used gas mixtures analyzed on the Haldane apparatus. in some patients when it was necessary to control Whole blood pH was determined using a glass ventilation manually. In all patients endotracheal electrode standardized with buffers of known pH. intubation was performed under suxamethonium Anaesthesia was then induced in the patient relaxation and the oxygen concentration in the and surgery commenced as soon as the patient anaesthetic mixture used for maintenance was was placed on the operating table; 15-30 minutes between 33 and 50 per cent. after the start of surgery, venous blood and Epidural analgesia was also used as an alternaarterialized capillary blood were collected from tive to general anaesthesia when it was suitable the patient for sickling and gas studies; 30 for the surgical procedure. Postoperatively, minutes after the cessation of surgery and anaes- oxygen was administered through a nasal catheter thesia, venous blood and arterialized capillary for at least 2 hours while the patients were in the blood were again collected for similar studies as recovery ward. indicated above. RESULTS The second part of this study consisted of reviewing the case notes of all patients known to The abnormal haemoglobins in the 24 patients have abnormal haemoglobin syndromes and who studied in relation to anaesthesia and surgery for have been subjected to surgery and anaesthesia sickling and blood-gases consisted of 4 SS, 4 SC, in the hospital over the past two years. These 5 AC and 11 AS. The mean numbers of sickled included all those studied for sickling and blood- cells obtained for the patients in each abnormal gases above and any that were done before the haemoglobin group at 0, 15, 30, 45 and 60 haemoglobin electrophoresis results were avail- minutes were calculated. Figure 1 represents the able or when facilities for blood-gas studies were results obtained from plotting these mean sickled not available. cell values against time for patients with abnormal haemoglobin SS during the pre-, intra- and postoperative periods. It would appear that anaesAnaesthesia. Premedication consisted of atropine and thesia did not increase the sickling tendencies of moderate doses of pethidine (50-75 mg) in the cells.

PATIENTS WITH ABNORMAL HAEMOGLOBIN SYNDROMES

1161

60-1

40-,

c o

20100-

TIME (Minutes) FIG. 1 Mean sickling rate (SR) in relation to time in 4 SS patients. Dots represent pre - operative mean sickling rate. Crosses represent intra-operative mean sickling rate. Open circles represent postoperative mean sickling rate.

TIME (Minutes) FIG. 2 Mean sickling rate (SR) in relation to time in 4 SC patients. Dots represent pre - operative mean sickling rate. Crosses represent intra-operative mean sickling rate. Open circles represent postoperative mean sickling rate.

15 30 45 60 TIME (Minutes)

FIG. 3 Mean sickling rate (SR) in relation to time in 11 AS patients. Dots represent pre - operative mean sickling rate. Crosses represent intra-operative mean sickling rate. Open circles represent post' operative mean sickling rate.

TABLE II

Details of anaesthetic agents and techniques used in 24 patients with abnormal haemoglobin syndromes—group I. Number of Technique Haemoglobinopathy anaesthetics Agents General anaesthesia Regional anaesthesia

Halothane + nitrous oxide Trichloroethylene + nitrous oxide Nitrous oxide + relaxant Epidural

2 SS, 3 AC, 5 AS 1 SS, 1 AC, 3 AS 1 3SC, 1 AC, 3 AS 1 SC

10

ss,

S 1

Total

24

5

Figures 2 and 3 represent data obtained from tion than in the pre-operative or postoperative plotting the mean numbers of sickled cells period for each group. With regard to the mean against time for patients with haemoglobin SC PEICO, and pH, these were only slightly altered and AS respectively during the pre-, intra- and during or after anaesthesia from their pre-operapostoperative periods. The number of sickled tive values. In the AS group, there was one cells at 1 hour obtained for these abnormal patient with Fallot's tetrad and the values of the haemoglobin groups appeared not to have been blood-gases in this patient have been presented increased by the effects of anaesthesia, during or separately from the others because of the expected after the surgical procedures. As expected, the low arterial oxygen tension in this condition. samples of blood from haemoglobin AC patients Table II shows the anaesthetic agents used in did not sickle. these 24 patients and the distribution of the Table I shows the mean values of the blood- abnormal haemoglobins. gases obtained before, during and after operation In the second part of the study, 33 patients for the different abnormal haemoglobin groups. (5 SS, 5 SC, 5 AC and 18 AS) underwent 50 The mean Pao2 was much higher during opera- surgical and anaesthetic procedures; some of the

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

in

Mean

30-

1162

BRITISH JOURNAL OF ANAESTHESIA

TABLE

III

Operations performed on patients with abnormal haemoglobin syndrome, 1969-70 (inclusive). Number Ear, nose and throat (tonsillectomy, Cadwell-luc) 4 Thyroidectomy 2 Oesophagoscopy and bouginage 8 Upper abdominal surgery (gastrectomy, vagotomy and pyloroplasty, liver biopsy, splenectomy) ... 5 Lower abdominal surgery (transverse colectomy, abdo-perineal excision, closure of colostomy) ... 4 Burr-holes 2 Haemorrhoidectomy 2 Thoracotomy (Blalock, ligation of PDA, pericardiectomy) 3 Orthopaedic surgery (laminectomy, open reduction of fracture, sequestrectomy and debridement) ... 11 Genito-urinary (repair of hypospadias, excision of urachal cyst, exploration of kidneys, ureteric catheterization) 4 Obstetrics (Caesarean section) 1 Gynaecological ( W F repair) 2 Lipoma (excision) 1 Carotid angiogram 1 Total 50

TABLE V

Complications in SO surgical procedures on patients with abnormal haemoglobin syndromes. Haemoglobino- No. of pathy patients

ss sc

AC AS

Total

No. of procedures Complications

5 18

6 6 15 23

33

50

5 5

nil nil nil

2 deaths

Case 1. A 50-year-old male had a 2-week history of abdominal discomfort and abdominal mass. Preoperatively, he was slightly jaundiced, but liver function tests, haematocrit, prothrombin time, serum calcium, phosphate and electrolytes were all within normal limits. Anaesthesia was induced with thiopentone 300 mg given intravenously, and endotracheal intubation performed under suxamethonium bromide 40 mg given intravenously. Anaesthesia was maintained with a mixture of nitrous oxide and oxygen and pancuronium was used to produce total muscular relaxation, ventilation being controlled manually. At laparotomy the patient was found to have a tumour of the pyloric end of the stomach with multiple carcinomatous nodules in the liver. The immediate postoperative condition of the patient was quite good. On the 4th postoperative day, the patient developed hiccup, increasing jaundice, and on the 13th postoperative day he passed about 400 ml of altered blood per rectum. His condition deteriorated and he died on the 15th postoperative day. Case 2. A 26-year-old woman had a 3-year history of fluctuant swelling on the back over the 12th left rib, and weakness of both legs and also loss of bladder function. She was found to have crushed lumbar vertebrae with flaccid paraplegia and cauda equina lesion, and a presumptive diagnosis of tuberculosis of the spine was made. Surgery was delayed as she was found to have crepitations with diminished air entry over the right middle and lower lung zones. After 2 weeks of physiotherapy, breathing exercises, and antibiotics, a dorso-lumbar laminectomy was performed under general anaesthesia. Anaesthesia was induced with thiopentone 200 mg followed by suxamethonium bromide

TABLE IV

Details of anaesthetic agents and techniques during SO procedures on 33 patients with abnormal haemoglobin syndromes—group II. Number of Haemoglobinopathy Technique Agents anaesthetics General anaesthesia

Regional anaesthesia

Halothane Trichloroethylene + nitrous oxide Ether + nitrous oxide Nitrous oxide + relaxant Ketamine Epidural

3 SS, 9 AC, H A S 1 SS, 3 AC, 3 AS 2 SC, 2 AC 1 SS, 3 SC, 1 AC, 8 AS 1SS 1 SC, 1 AS

23 7 4 13 1 2

Total

50~

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

patients underwent more than one operative procedure. Table III shows the surgical procedures carried out on these patients while the anaesthetic techniques and agents used are shown in table IV. Halothane was the most popular anaesthetic agent, and was followed by the use of nitrous oxide and relaxant with manual control of ventilation. Table V shows the complications that resulted from the 50 surgical and anaesthetic procedures. There were no complications except in 2 patients who had AS haemoglobin.

PATIENTS WITH ABNORMAL HAEMOGLOBIN SYNDROMES 40 mg, oxygenation and endotracheal intubation. Anaesthesia was maintained with a 50/50 mixture of nitrous oxide and oxygen, ventilation being controlled manually and tubocurarine being injected to produce muscular paralysis. An extensive extradural mass was found with thickened dura and adhesions round the nerve roots. The immediate postoperative course was good but on the 14th postoperative day she collapsed suddenly, with severe breathlessness, and died within a few minutes. A presumptive diagnosis of pulmonary embolization was made as permission for autopsy examination was not granted.

Browne (1965) reported that there was no complication in his 16 patients with sickle-cell anaemia subjected to surgery in the West Indies; 9 of these received general anaesthesia while the rest had regional analgesia. Gilbertson (1965) reported 2 deaths among the 3 patients with sickle-cell anaemia subjected to general anaesthesia in West Africa, whereas there were only 2 with postoperative complications among his 33 patients with haemoglobin SC disease. In the University College Hospital, Ibadan, we have had the impression over the past few years that the results of surgery and anaesthesia in our patients with abnormal haemoglobin syndromes including those with sickle-cell anaemia have been quite good. In the present study, although the number of patients involved is small for statistical evaluation, it should be noted that there was no morbidity or mortality among the 27 anaesthetic procedures carried out in 6 SS, 6 SC and 15 AC patients. Among the 23 procedures in the patients with AS haemoglobin there were 2 deaths. It is difficult to attribute the death of the patient who had advanced carcinoma of the stomach with multiple metastatic nodules in the liver to his abnormal haemoglobin state, remotely or otherwise. In the second patient who had been bed-ridden for a long time because of her paraplegic condition, the circulatory stasis in her limbs may have precipitated thrombus formation and subsequent embolization. It is possible that the abnormal haemoglobin state in this woman could have aggravated the circulatory stasis and contributed to her death. It has been recognized since the in-vitro investigations of Emmel (1917) that variations in the tension of oxygen in the circulation can affect the number of cells sickled. Emmel observed sickled cells in sealed coverslip slides of

erythrocytes from sickle-cell anaemia patients. Later, Daland and Castle (1948) introduced the in-vitro use of sodium metabisulphite to remove oxygen from the blood sample and induce sickling of red blood cells in sickle-cell anaemia. Although various other procedures, involving e.g. E. coli cultures, sodium dithionite, faeces and bubbling nitrogen through the blood, have been used, the method used here has the double advantage of studying sickling in a physiological milieu whilst allowing graded observations to be made throughout the duration of the incubation (1 hr). An estimate of both the rate of sickling and the total amount sickled is thus possible. Various hypoxic situations such as flying in unpressurized aircraft, are known to increase sickling. Since, however, these surgical procedures were not accompanied by lowering of Pa 02 , the sickling rate would not have been expected to rise and it did not. There was no appreciable change in PaC02 or pH during these procedures, and the possible alteration in sickling tendency consequent on changes in PaCo2 and pH were not seen. Among the anaesthetic agents used in this series, it would appear that none was found to have any deleterious effect on patients with abnormal haemoglobins as judged by the counts of sickled cells and the morbidity or mortality results. It is our impression that no particular anaesthetic agent or technique is contraindicated in patients with abnormal haemoglobin syndromes; what may be more important is how these agents and techniques are used. It is important to note that the inspired oxygen concentration during general anaesthesia in this series was between 33 and 50 per cent. Even though Reinhard and associates (1944) have shown that prolonged oxygenation of 4-5 days' duration may cause depression of erythropoiesis in patients with sickle-cell anaemia, the concentration of oxygen used during and after anaesthesia in this study has not been found harmful. From the experience that has been gained in this hospital, it may be useful to make some recommendations in respect of anaesthesia and surgery in patients with abnormal haemoglobin syndromes. (1) Haemoglobin electrophoresis must be done routinely on all patients in areas where

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

DISCUSSION

1163

1164

(3) Blood transfusion should be used with caution and only after very careful cross-matching, and the blood given should contain haemoglobin AA or AC cells. It is important to remember that the patients with SS or SC abnormalities often have cardiomegaly, increased cardiac output, and increased plasma volume; cardiac failure can very easily complicate blood transfusion.

(4) Bearing in mind the factors concerned in the concept of available oxygen (available O 2 = cardiac output x 1.34 x Hb concentration x % saturation), it would be wise to replace blood as it is being lost during surgery and also ensure that the cardiac output is maintained as near normal as possible. (5) In areas where abnormal haemoglobin syndromes are endemic, it would be wise to avoid the routine use of vascular tourniquet unless the patient's haemoglobin electrophoresis is known to be AA. This follows from the work of Harris and associates (1956) who demonstrated that localized statis in the capillaries, with accumulation of carbon dioxide and other acid metabolites causes a fall in pH, which enhances sickling. However, Gilbertson (1965) has reported the successful use of tourniquet in patients with AS haemoglobin after careful exsanguination of the limb with an Esmarch bandage. (6) It is essential to ensure adequate ventilation and adequate oxygenation during anaesthesia and in the immediate postoperative period; there should be neither respiratory depression nor respiratory obstruction. The reason for this is that hypoxia is known to provoke intravascular sickling. The oxygen concentration in the inhaled anaesthetic mixture should be between 33 and 50 per cent, and oxygen should also be given postoperatively for a couple of hours through a nasal catheter at a rate of 2 l./min in adults. The work of Nunn and Payne (1962) and Conway and Payne (1964) shows that hypoxia is not infrequent postoperatively even after an uneventful anaesthetic procedure. Therefore, oxygen therapy would be beneficial to these patients postoperatively. However, it would be wise to avoid prolonged use of 100 per cent oxygen in these patients as it has been suggested (Reinhard et al., 1944) that this may depress erythropoiesis when used for 4-5 days. (7) As far as the circulation is concerned, hypotension, hypovolaemia and localized stasis should be avoided, as these may lead to metabolic acidosis and tissue hypoxia. Greenberg and Kass (1958) have shown that acidosis enhances sickling. Alkali therapy may be of some beneficial value as Nwokolo (1960), Lehmann (1963) and HughJones, Lehmann and McAlister (1964) found that

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

abnormal haemoglobin syndromes are endemic before major elective surgical procedures are undertaken so that extra care can be given to such patients. (2) Elective surgery must be scheduled at a time when the patient is well and is neither jaundiced nor in "crisis". As regards the level of haemoglobin which should be reached before the patient's condition is acceptable for elective or emergency procedures, there should be some flexibility about this; the general state of the patient is just as important as the haemoglobin level. As a guideline, haematocrit level required for minor surgery may not be as high as that required for major surgery but it should not have deviated much from the patient's usual level. For major surgery the haematocrit should be at least 30 per cent. The low oxygen tension which has been found in some of these abnormal haemoglobin syndromes (Fraimow et al., 1958; Ryan and Hickam, 1952; Oduntan, 1969), and also the low haemoglobin concentration, do not necessarily imply a shortage of oxygen supply to the tissues because of some compensatory mechanisms which are brought into play. One of these compensatory mechanisms was that suggested by Bellingham and Huehns (1968) who showed that the low oxygen affinity found in the abnormal haemoglobins S or C allows oxygen to be given up adequately and readily at the tissue level. Also Eaton and Brewer (1968) and Benesch and Benesch (1969) have shown that 2:3 diphosphoglycerate (DPG) in the red cells lowers oxygen affinity of haemoglobin and thus facilitates oxygen unloading because DPG is preferably bound to deoxyhaemoglobin. These compensatory mechanisms suggest that these patients should be quite readily acceptable for surgery in spite of their anaemic state, provided their general condition is good and the haematocrit is not too low.

BRITISH JOURNAL OF ANAESTHESIA

PATIENTS WITH ABNORMAL HAEMOGLOBIN SYNDROMES

ACKNOWLEDGEMENTS

We wish to express our sincere gratitude to our anaesthetic and surgical colleagues, as well as to the nursing staff, University College Hospital, Ibadan, who have also helped in the care of these patients. We also thank Messrs F. Obodairo and V. Okuyemi for technical assistance and Mr F. O. Oni for secretarial assistance. REFERENCES

Bauer, J. (1958). Sudden unexpected death. J. Mich, med. Soc, 27, 729. Bellingham, A. J., and Huehns, E. R. (1968). Compensation in haemolytic anaemias caused by abnormal haemoglobins. Nature (Lond.), 218, 924. Benesch, R., and Benesch, R. E. (1969). Intracellular organic phosphates as regulators of oxygen release by haemoglobin. Nature (Lond.), 221, 618. Browne, R. A. (1965). Anaesthesia in patients with sickle-cell anaemia. Brit. J. Anaesth., 37, 181. Ciliberti, B. J., Mazzia, V. D. B., Mark, L. C , and Marx, G. F. (1962). Clinical Anesthesia Conference: sickle-cell disease and anesthesia. N.Y. St. J. Med., 65, 548.

Conway, C. M., and Payne, J. P. (1964). Hypoxaemia associated with anaesthesia and controlled respiration. Lancet, 1, 12. Daland, G. A., and Castle, W. B. (1948). A simple and rapid method for demonstrating sickling of the red blood cells: the use of reducing agents. J. Lab. din. Med., 33, 1082. Eaton, J. W., and Brewer, G. J. (1968). The relationship between red cell 2:3 diphosphoglycerate and levels of hemoglobin in the human. Proc. nat. Acad. Sci. (Wash.), 61, 756. Emmel, V. E. (1917). A study of the erythrocytes in a case of severe anemia with elongated and sickle shaped red blood corpuscles. Arch, intern. Med., 20, 586. Fraimow, W., Rodman, T., Close, H. P., Cathcart, R., and Purcell, M. K. (1958). The oxyhemoglobin dissociation curve in sickle cell anemia. Amer. J. med. Sci., 236, 225. Gilbertson, A. A. (1965). Anaesthesia in West African patients with sickle-cell anaemia, haemoglobin SC disease, and sickle-cell trait. Brit. J. Anaesth., 37, 614 Greenberg, M. S., and Kass, E. H. (1958). Studies on the destruction of red blood cells. XIII: Observations on the role of pH in the pathogenesis and treatment of painful crisis in sickle-cell disease. Arch, intern. Med., 101, 355. Harris, J. W., Brewster, H. H., Ham, T. H., and Castle, W. B. (1956). Studies on the destruction of red blood cells. X: The biophysics and biology of sickle-cell disease. Arch, intern. Med., 97, 145. Holzmann, L., Finn, H., Lichtman, H. C , and Harmel, M. H. (1969). Anesthesia in patients with sickle cell disease: a review of 112 cases. Anesth. Analg. Curr. Res., 48, 4, 566. Hugh-Jones, K., Lehmann, H., and McAlister, J. M. (1964). Some experiences in managing sickle-cell anaemia in children and young adults, using alkalis and magnesium. Brit. med. J., 2, 226. Lehmann, H. (1963). Treatment of sickle-cell anaemia. Brit. med. J., 1, 1158.

Luzzatto, L., Nwachukwu-Jarrett, E. S., and Reddy, S. (1970). Increased sickling of parasitized erythrocytes as a mechanism of resistance against malaria in the sickle cell trait. Lancet, 1, 319. Nunn, J. F., and Payne, J. P. (1962). Hypoxaemia after general anaesthesia. Lancet, 2, 631. Nwokolo, C. W. (1960). The diagnosis and management of sickle-cell anaemia. W. Afr. med. J., 9, 194. Oduntan, S. A. (1969). Blood gas studies in some abnormal haemoglobin syndromes. Brit. J. Haemal., 17, 535. Reinhard, E. H., Moore, C. V., Dubach, R., and Wade, L. J. (1944). The depressant effects of high concentrations of inspired oxygen on erythrocytogenesis; observations on patients with sickle cell anemia, with a description of the observed toxic manifestations of oxygen. J. clin. Invest., 23, 682. Rosenbaum, J. (1965). Fatal hemoglobin S-C disease crises following tonsillectomy. Arch. Otolaryng., 82, 307. Ryan, J. M., and Hickam, J. B. (1952). The alveolararterial oxygen pressure gradient in anemia. J. clin. Ivest., 31, 188. Shapiro, N. D., and Poe, M. F. (1955). Sickle cell disease: an anesthesiological problem. Anesthesiology, 16, 771.

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

the administration of sodium bicarbonate prevents the development of painful crises. We have not used bicarbonate therapy routinely in our patients, but it would seem particularly indicated if pH shows some degree of acidosis. The number of patients involved in this preliminary study is too small for a test of significance to be meaningful. However, it appears from these results that sickling is less during and after anaesthesia. If this is confirmed, then the reduced sickling is probably due to the high oxygen concentration in the inspired mixture resulting in high oxygen tensions during and after anaesthesia. Although more follow-up studies are in progress, it is our impression from this study that anaesthesia in patients with sickle-cell anaemia in West Africa could be associated with low morbidity and mortality, as has also been found by Browne (1965) among his patients with sicklecell anaemia in the West Indies. In this respect, our experience does not agree with that of Gilbertson (1965) who reported very high mortality in patients with sickle-cell anaemia in West Africa. The percentage of oxygen in the anaesthetic mixture used in these studies may be important. The high inspired oxygen concentration of 33-50 per cent in this series and in Browne's (1965) series were unaccompanied by sickling problems, unlike in Gilbertson's series where the concentration was 25 per cent.

1165

1166

BRITISH JOURNAL OF ANAESTHESIA

ANESTHESIE MISE EN OEUVRE CHEZ DES MALADES PRESENTANT DES ANOMALIES DE L'HEMOGLOBINE: ETUDE PRELIMINAIRE SOMMAIRE

NARKOSE IN PATIENTEN MIT ABNORMEN HAMOGLOBIN-SYNDROMEN: VORLAUFIGER BERICHT ZUSAMMENFASSUNG

In 24 Operations Patienten mit abnormen Hamoglobinen (4 SS, 4 SC, 5 AC und 11 AS) wurden vor, wahrend und nach einer Narkose Sichelzellenbildung und Blutgas-Spannung untersucht. Die mittlere Anzahl

ANESTESIA EN PACIENTES CON SINDROMES DE HEMOGLOBINA ANORMAL: UNA COMUNICACION PRELIMINAR RESUMEN

Estudios sobre la tendencia desarrollar hematies falciformes en la sangre y sobre los gases sanguineos fueron efectuados antes, durante y despues de la anestesia en veinticuatro pacientes con hemoglobinas anormales (4 SS, 4 SC, 5 AC y 11 AS) sometidos a intervenciones quirurgicas. Los numeros promedios de celulas falciformes por hora obtenidos para estos grupos de hemoglobina anormal no fueron aumentados por los efectos de la anestesia. Por lo que a las tensiones de los gases sanguineos se refiere, la Pao2 media fue mucho mas elevada durante la anestesia que durante los periodos pre- y postanestesicos, mientras que la Paoo2 y el pH no estaban muy alterados. En la segunda parte de este estudio fueron revisados los registros anestesicos y postoperatorios de treinta y tres pacientes con hemoglobinas anormales (5 SS, 5 SC, 5 AC y 18 AS) sometidos a cincuenta intervenciones quirurgicas. Solamente fueron registrados dos muertes y estas ocurrieron en el grupo de hemoglobina AS. La muerta no estaba relacionada con la presencia de hemoglobina anormal en un caso, mientras que esta relacion no puede ser totalmente excluida en el otro caso. Son propuestas algunas recomendaciones sobre los cuidados anestesicos de estos pacientes.

THE FOURTH INTERNATIONAL MEDICAL FILM FESTIVAL organized by the Cercle de Medecine de l'Universite Libre de Bruxelles will take place in Brussels on March 4-11, 1972, in the locale of the University. Official languages: English, French. Inquiries to: Secretariat du Cercle de Medecine, rue aux Laines 162, 1000 Bruxelles. Telephone: 02/38.49.15.

Downloaded from http://bja.oxfordjournals.org/ at University of California, Santa Barbara on June 29, 2015

Des examens portant sur la drepanocytose et les gaz du sang ont ete effectues avant, pendant et apres l'anesthesie, chez 24 malades presentant des anomalies de l'hemoglobine (4 SS, 4 SC, 5 AC et 11 AS) et soumis a des interventions chirurgicales. Le nombre moyen de cellules falciformes obtenu par heure pour ces series de malades presentant des anomalies de l'hemoglobine, n'a pas ete accru du fait de l'anesthesie. Dans la mesure ou il existait un retentissement de l'anesthesie sur les tensions des gaz du sang, la tension moyenne d'oxygene Pao3 etait beaucoup plus elevee au cours de l'anesthesie que dans les periodes pre- et post-anesthesiques, tandis que la tension de gaz carbonique Paco2 et le pH n'etaient pas sensiblement modifies. Dans la seconde partie de cette etude, on a reexamine les protocoles anesthesiques et post-operatoires concernant trentetrois malades atteints d'anomalies de l'hemoglobine (5 SS, 5 SC, 5 AC et 18 AS) et qui avaient ete soumis a 50 interventions chirurgicales. On n'a note que deux cas de deces seulement et ceux-ci interessaient le groupe de l'hemoglobine AS. Dans un cas, l'exitus lethalis n'etait pas en rapport avec l'anomalie hemoglobinique, alors que le role de cette derniere ne pouvait pas etre exclu dans le second. Quelques recommandations sont proposees en ce qui concerne les mesures a mettre en oeuvre du point de vue anesthesique chez de tels malades.

an Sichelzellen pro Stunde wurde durch die Narkose nicht erhoht. Bei der Blutgas-Untersuchung erwies sich der mittlere Paoj wahrend der Narkose als sehr viel hoher als vor- und nachher; Paoo2 und pH waren kaum verandert. Im zweiten Teil der Untersuchung wurden die Daten von 33 Patienten mit abnormen Hamoglobinen (5 SS, 5 SC, 5 AC, 18 AS) aus 50 Operationen iiberpriift. Darunter waren nur zwei Todesfalle in der AS-Gruppe. In einem dieser Falle bestand keine Beziehung zwischen Tod und Anomalie, im anderen Fall konnte eine solche nicht eindeutig ausgeschlossea werden. Einige Empfehlungen fiir die Narkose derartiger Patienten werden gegeben.