Management options

All units should offer counselling and testing for at-risk women prenatally or even pre-pregnancy, and this should continue during pregnancy. Many units have protocols in place for joint management of HIV-positive women by obstetricians and HIV specialists.

Acute HIV infection is rarely a known problem on the labour ward and in general is managed as for any acute viral illness. For those with acute organ dysfunction, supportive management is directed at the organ system affected.

Patients with chronic HIV infection are managed according to their degree of organ impairment, which in most cases presenting to the labour ward will not be severe. All systems may be affected, either by primary HIV infection or secondary infection, e.g. with fungi or other atypical organisms. Neurological manifestations are especially important to anaesthetists and include neuropathy, encephalopathy, meningitis, focal brain lesions, dementia, myelopathy and myopathy. In addition, HIV-positive subjects' life expectancy is increased by taking prophylactic highly active antiretroviral therapy (HAART). These drugs may cause blood dyscrasias, gastrointestinal disturbances, neurological and hepatic impairment and increased drug metabolism via hepatic enzyme indication. Prior to any anaesthetic intervention all patients must therefore be assessed carefully for evidence of organ system impairment.

In general, patients with HIV infection are managed as for any obstetric patient, unless specific contraindications exist. Particular care with invasive techniques has been suggested, to reduce the risk of introducing infection, but standard aseptic methods should be adequate if they are followed. The use of epidural or spinal anaesthesia has been questioned for fear of seeding the virus into the cerebrospinal fluid (CSF) and thus accelerating the central nervous system (CNS) progression of the infection; seeding opportunistic infective organisms into the CNS; and complications related to underlying and undiagnosed CNS pathology. Since CSF involvement occurs very early in HIV infection, no further risk is generally felt to exist, and this is supported by clinical experience, albeit limited. Epidural blood patch has also been performed in HIV-positive patients without apparent adverse consequences. There has been no report of secondary CNS infection introduced during administration of regional anaesthesia in the HIV-infected mother and this risk is generally felt to be theoretical only. Further, if no evidence of CNS involvement exists then most authorities recommend regional anaesthesia as routine. If CNS abnormalities do exist then management is dependent on their severity and other considerations such as the presence of other complications.

Most units now treat HIV-positive mothers with antiviral drugs, e.g. zidovudine, which has been shown to reduce transmission to the neonate by up to two-thirds. Combination with elective Caesarean section reduces the risk further, to about 1%, although some authorities have suggested that vaginal delivery is an acceptable option in the UK since the risk of vertical transmission has fallen to ~1% if the mother is well controlled on HAART. There is wide consensus that breastfeeding should be discouraged.

Because of the implications of testing for HIV, most health authorities advocate the approach of 'universal precautions' to potentially at-risk patients; thus routine management of all women on the labour ward should involve the use of protective clothing where appropriate (gloves, goggles etc., according to individual choice), use of disposable equipment or proper sterilisation techniques and careful handling and disposal of contaminated sharps. If these practices are routinely followed, the known HIV-positive patient should need no extra measures. Many units have policies such as this and have accepted the cost implications of such all-inclusive guidelines, especially given the high cost and high profile of legal proceedings against establishments where cross-infection has occurred. If an accidental needle-stick injury or similar event occurs, local protocols and specialists should be consulted for guidance about prophylactic zidovudine therapy, since this is a controversial area. The risk of seroconversion after needlestick is about 0.3%.

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