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38 Haemoglobinopathies

end organ damage. Preventive measures have therefore focused on • Early diagnosis of a haemoglobinopathy is essential for appropriate
measures designed to prevent sickling. management; the onus lies with the medical team to suspect it in at-
Newer models of sickle cell disease have suggested, however, that risk groups and with certain typical presentations.
chronic vascular inflammation and endothelial dysfunction may instead • Education of patients and their parents about their condition can
underlie many of the pathological processes. The logic behind measures help to avoid dangerously late presentations. Parents of infants with
aimed primarily at preventing sickling has been called into question. sickle cell disease should be taught how to palpate their infants’
An example of such a measure is the common practice of exchange spleens and when to suspect a splenic crisis; warning signs of other
transfusion prior to undertaking surgery. The idea is to dilute the sickle serious complications should also be discussed.
haemoglobin with normal red cells, thereby decreasing the risk of
intraoperative sickling. Nevertheless, there is no evidence to suggest • Penicillin prophylaxis reduces the incidence of infection in children
0
the superiority of this approach over a simple “top-up” transfusion; with sickle cell anaemia and heterozygotes with HbS-β thalassae-
indeed, the case for universal preoperative transfusion remains to be mia. This preventive treatment should be started between 2 and 4
definitively proven (see Table 7.4). months of age and continued at least until the age of 5.
It has been suggested that laparoscopic surgery could diminish the • All children with sickle cell disease and splenectomised children
risk of sickle-related complications for patients undergoing abdominal with thalassaemia should receive immunisation against pneumococ-
surgery, but this has not been demonstrated to date. Patients undergoing cus, H. influenzae, meningococcus, influenza, and Salmonella typhi
laparoscopic surgery have been shown to have shorter hospital stays, (in endemic areas) as well as routine vaccines. Hepatitis B vaccina-
however, so, where feasible, a laparoscopic approach should be considered. tion should be considered in all children with a haemoglobinopathy.
Current advice for the perioperative management of children with
sickle cell disease is as follows: • Careful foot care and well-fitting shoes can help to prevent the
development of leg ulcers.
• All teams involved in the patient’s surgery should be aware of the
diagnosis of sickle cell disease and the need for special attention. Evidence-Based Research
• Preoperative assessment should consider the following indicators of Table 7.4 presents a study comparing preoperative transfusion regimes
increased operative risk in patients with sickle cell disease: for patients with SCD.
Table 7.4. Evidence-based research.
- frequent recent hospitalisations;
- sickle cell lung disease; Title Preoperative blood transfusions for sickle cell disease
- history of early onset dactylitis (a predictor of severe disease); Authors Hirst C, Williamson L
- coexisting chest or urinary tract infection; and Institution AstraZeneca, Alderley Park, UK.
- previous stroke. Reference Cochrane Database of Systematic Reviews 2001, Issue 3.
Problem There is a high rate of perioperative complications in
• Simple transfusion to achieve a haemoglobin concentration of patients with sickle cell disease.
approximately 10 g/dl should be performed before all but the low-
est risk procedures. Intervention Preoperative blood transfusion.
Comparison/ This study is a meta-analysis of two randomised controlled
• Careful attention should be paid to avoiding hypoxia, although this control trials comparing an aggressive preoperative transfusion
should not preclude the use of opiate analgesia for pain manage- (quality of regimen, designed to decrease the sickle haemoglobin
ment or anxiolytic medication, if required. evidence) level to less than 30%; a conservative regime, designed
to increase the haemoglobin level to 10 g/dl; and a group
• Dehydration and hypothermia should be avoided. receiving no preoperative transfusion.
Outcome/ The study found that the conservative transfusion regime
• Early mobilisation, effective postoperative pain control, and chest effect was as effective as the aggressive regimen in preventing
physiotherapy with incentive spirometry may decrease the risk of surgical complications, and was associated with fewer
chest complications. transfusion-related adverse events. There was insufficient
evidence to demonstrate a clear advantage to preoperative
Prevention blood transfusion compared with a nontransfused group.
Many of the conditions discussed in this chapter are unavoidable Historical The potential risks associated with blood transfusions vary
manifestations of a group of complex multisystem diseases. A number significance/ significantly according to the setting. In areas of the world
where resources are limited, and clean, infection-free blood
of measures could improve the outcomes for these children, however, comments products cannot be guaranteed, a risk-benefit analysis is likely
including those listed here. to favour less frequent usage of preoperative transfusions.

Key Summary Points

1. Haemoglobinopathies (sickle cell disease/thalassaemias) are 4. A multidisciplinary team approach is needed.
associated with increased morbidity and mortality. 5. Careful perioperative management is required to minimise
2. Due to the surgical manifestations of haemoglobinopathies, the risk of surgical complications, including the consideration
surgical intervention is a common occurrence and is of blood transfusion prior to surgical procedures, paying
associated with a higher risk of complications for these patients careful attention to oxygenation and hydration in the intra- and
than for the general population. postoperative period, providing adequate pain control, and
encouraging early mobilisation.
3. Basic knowledge of the pathophysiology of sickle cell disease
and the principles behind its clinical management is essential
for the paediatric surgeon to achieve successful outcomes in
sickle cell patients under their care.