Summary
In study session IX you have learnt
- The human immunodeficiency viruses, HIV-l and HIV-2, Virus that causes acquired immune deficiency syndrome, are retroviruses that attach to cells with CD4+ surface antigen (predominantly helper T lymphocytes) and ultimately replicate by integrating virally produced deoxyribonucleic acid (DNA) into the nucleus of the host cell.
- Acquired immune deficiency syndrome (AIDS) is an advanced stage of HIV in which many life threatening infection will occur because the body becomes incompetent to resist infection.
- The immune system protects the body by recognizing antigens (bacteria, viruses, fungi, and parasites) on invading bacteria and viruses and reacting to them. An antigen is any substance that induces a state of sensitivity and immune responsiveness.
- B Lymphocytes can recognize specific antigen targets and can secrete specific antibodies. T lymphocytes have two major functions: regulation of the immune system and killing of cells that bear specific target antigens.
- Host cells infected with HIV have a shortened life span as a result of the virus's using them as "factories" to produce multiple copies of new HIV.
- The HIV life cycle includes six phases; binding and entry, reverse transcription, integration, replication, budding, and maturation
- The pathogenesis of HIV is basically a struggle between HIV replication and the immune responses of the patient, via cell-mediated and immune-mediated reactions. There are many mechanisms of CD4+ cell depletion by HIV infection.
- There are different clinical stages of HIV infection classified depending on the clinical severity, CD4+ and viral load.
- Every organ system in the body can be affected as a direct consequence of infection, opportunistic infection or the effects of ART. Different types of heart disease, anemia, bleeding and hyper coagulation problem, nerve problem, and other system will be affected.
- Preoperative assessment consists of the history, physical examination, and laboratory studies. The history should include evaluation of opportunistic infections and malignancy and concurrent treatments with antiretroviral or anti opportunistic drugs.
- The laboratory work-up should include complete blood count, clotting functions, and glucose, liver, and renal function tests.
- Chest radiograph and electrocardiogram should be performed
- Infection control preparation including universal precautions with gloves, aprons, visors (eye glass) etc.
- Minimize interruptions in ARV therapy as possible to diminish drug resistance
- Consider drug interactions with ARV with use of drugs affected by hepatic enzyme inhibition and/or induction for example:
- Pulmonary complications can occur as a consequence of opportunistic infections. This may lead to respiratory distress and hypoxemia, aggravated by a decrease in functional residual capacity seen during pregnancy. Regional anesthesia may be a preferable technique in these patients. However, a high motor block with intercostal muscle paralysis may not be tolerated. Regional anesthesia was shown to be associated with reduced morbidity and mortality in a wide range of patients, including treated HIV parturient having cesarean delivery under spinal anesthesia.
- Increased intra cranial pressure and central nervous systemic infections (meningitis, encephalopathy, or myelopathy) are contraindications to spinal anesthesia.
Last modified: Sunday, 20 November 2016, 6:14 PM