Anesthetic Management

Anesthetic Management

Pre Anesthetic Assessment

In addition to a routine preanesthetic assessment the following should be considered for a patient with HIV.

• 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.
• Assessment of risk and coexisting diseases during preoperative evaluation should focus on the patient's status, type of surgery, and anesthesia, stage of HIV infection, the immunologic status (CD4 cell count), and the coexistence of opportunistic infections and malignancies, should allow a good prediction for the perioperative risk of the HIV-patient to be construed.
• The laboratory work-up should include complete blood count, clotting functions, and glucose, liver, and renal function tests. Verification of the immunological status, i.e
• Chest radiograph and electrocardiogram should be performed in all patients.
• Patients with a history or signs of cardiac or pulmonary dysfunction should undergo a more thorough evaluation by respective specialty

Intraoperative Anesthetic Consideration

• 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:
Opioids: The effects of fentanyl may be enhanced by ritonavir due to both liver enzyme inhibition and induction. Enzyme inhibition reduces fentanyl clearance and enzyme induction increases metabolism to active metabolites such as normepiridine.
Benzodiazepines: Saquinavir may inhibit midazolam metabolism.
Calcium channel blockers may have enhanced hypotensive effects due to enzyme inhibition.
Local anesthetics such as lignocaine may have increased plasma levels due to enzyme inhibition.
Neuromuscular blockers effect may be prolonged, even a single dose of vecuronium for instance.
• Strict aseptic technique to be exercised as HIV infected patients are immune-compromised and are susceptible to bacterial infections
• The anaesthetic plan should be tailored to the individual patient and the type of surgery as appropriate.
• 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.
• Opportunistic infections may be associated with increased complications; surgery should be postponed whenever possible when these infections are present.
• Increased intra cranial pressure and central nervous systemic infections (meningitis, encephalopathy, or myelopathy) are contraindications to spinal anesthesia.
• Radiological studies of the spinal cord should be performed as part of the neurological evaluation to exclude compressive lesions in symptomatic patients. This is particularly important in a patient scheduled for a surgical procedure under regional anesthesia.
• Propofol and NRTIs may both potentially promote mitochondrial toxicity and lactic acidosis and it may be wise to avoid propofol infusions in patients receiving ARVs.