However, TIVA provides an alternative technique in which agents are delivered entirely via a syringe pump, without GA. Less than 20% of anaesthetists currently use TIVA to maintain anaesthesia, despite the potential benefits it offers.
TIVA can be performed using a combination of drugs, with the most utilised groups of drugs including hypnotics and short-acting opioids.
Two of the most common drugs are remifentanil and propofol. Propofol has revolutionised IV anaesthesia since it became widely available in the mid-1980s. Usually, there is a relatively rapid and clear-headed recovery it provides patients.1 For this article, the discussion of TIVA will refer mostly to anaesthesia induced and maintained through intravenous infusion.
Aside from being the only option when anaesthesia maintenance through inhalation agents is not possible, for example, during airway surgeries, there are many reasons that clinicians may choose to use TIVA.
One of the most reported consequences of TIVA is its positive effects on post-operative nausea and vomiting (PONV), which affects up to 27% of patients and costs healthcare systems billions in additional patient costs.3
A review across 229 randomised control trials looking at 20,991 patients found that those anaesthetised using TIVA had reduced PONV compared to GA.2
Additionally, a study in 2015 looked at 80 females undergoing thyroid surgery who were prospectively recruited and randomised between two groups: those undergoing TIVA and those where anaesthesia was maintained through desflurane inhalation with manual infusion of remifentanil (DES). The study found that those who had TIVA experienced a significantly better recovery.4
The implication is that TIVA potentially offers a cost-saving alternative that results in better patient recovery and experience.
Hospitals have day case targets of 75% in the UK16. TIVA has also been shown to aid in hitting these targets by reducing patients' time in the PACU. At a time when waiting lists are growing and hospitals are at full capacity, faster discharge of patients has become more essential, to free up bed space and allow for more patients to be treated. Furthermore, the reduced post-operative pain through the use of TIVA could mean that patients do not need to be monitored overnight, helping hospitals to achieve these targets.
There is some evidence from a literature search of randomized controlled trials in adults that TIVA with propofol may improve acute postoperative analgesia after surgery, but different factors such as surgical procedures and anaesthetic/analgesic techniques may influence its effectiveness.17
TIVA can be used for many surgical procedures that require anaesthesia, but much work has been done to investigate the benefits of TIVA use across different specialties.
The importance of the perioperative period in cancer metastasis is known, which is why it is important to consider all aspects of surgery when looking at how to improve survival rates, including anaesthesia.
A study comparing the use of volatile anaesthetics and TIVA in oesophageal cancer surgery found that although there was no difference in the cancer recurrence rate between the two, patients who underwent TIVA had a better survival rate.
In the entire cohort, the overall mortality rate during follow-up was 41.4% (382/922) in all patients, 51.3% (98/191) in the VA group, and 36.4% (284/731) in the TIVA group.8
ENT
TIVA doesn’t rely on normal pulmonary function to administer active agents. This means that it is well-suited to procedures on the upper airway, allowing for tubeless thoracic surgery.
When compared with general anaesthetic, it has been suggested that TIVA may improve surgical field quality, reduce blood loss and decrease operative time for endoscopic sinus surgery.9
Cardiology
TIVA agents like propofol and remifentanil offer many desirable characteristics that cardiac patients may benefit from, such as improved organ perfusion and protection, modulation of inflammation and brain protection.
TIVA may be recommended for cardiac surgery as when combined with comprehensive target-controlled drug delivery systems that can be adjusted to the specifics of cardiopulmonary bypass, it can be titrated safely and effectively in delicate and sick cardiac patients.10
Neurosurgery
The main function of anaesthesia in neurosurgery is to provide the patient with stable hemodynamics and reduced cerebral metabolism. Anaesthesia also needs to avoid intracranial hypertension and interfering with intraoperative neuromonitoring. It should also allow for rapid emergence from anaesthesia for neurological examination.11
Volatile anaesthetics (VA) have been shown to affect cerebral autoregulation12 and intracranial pressure13 which may mean that neurosurgery using VA have higher risks such as ischemic cerebral insults.11
Regarding hemodynamic stability, emergence times, extubation times, early cognitive function, and adverse events, TIVA is similar to volatile anaesthetics. However, several prospective, randomised trials suggest that increased intracranial pressure can be decreased while cerebral perfusion can increase in patients who received TIVA during craniotomy procedures.14
Robotic surgery
Robot-assisted Laparoscopic Radical Prostatectomy (RLRP) usually requires a steep Trendelenburg position and prolonged intraperitoneal carbon dioxide insufflation which results in increased intrabdominal pressure. This is known to cause peritoneal stretching and irritation, which can result in PONV.15
Anaesthesiologists should take additional steps to prevent PONV during RLRPs due to the increased risk of developing it. As mentioned previously, preventing PONV is important for both patients and hospitals.
TIVA has been shown to reduce PONV, with one study investigating its effects in patients undergoing RLRP. In the prospective single-site, double-blinded, randomized, and parallel-arm controlled trial, 62 patients were randomly assigned to the DES or TIVA group. The incidence of nausea in the post-anaesthetic care unit was 22.6% in the DES group and 6.5% in the TIVA (p=0.001) group. The post-operative incidence of nausea at 1-6 hours was 54.8% in the DES group and 16.1% in the TIVA group (p=0.001).15
Reducing emissions is increasingly becoming a priority for hospital systems as climate change is having an escalating impact on society. In the US alone, hospitals are responsible for up to 10% of greenhouse gas emissions.5 NHS England has already launched a net zero goal by 2050 which seeks to reduce emissions whilst still maintaining standards of patient care.
All volatile anaesthetics are potent greenhouse gases, with a range of global warming potential (GWP) from 440 to 6810 relative to carbon dioxide which has a reference of 1. These gases can have a big impact on the environment and their effects can be long-lasting. Nitrous oxide for example, which is commonly used, has a GWP of 289 and an atmospheric lifetime of around 120 years. Amsterdam University Medical Centre (UMC) has already banned nitrous oxide, desflurane and isoflurane which has seen their annual cannister use fall by 70%. 6
TIVA presents an alternative method of anaesthesia, which does not require the use of potent greenhouse gases.
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