Use of Hypotension Prediction Index may reduce Intraoperative Hypotension Outcomes, suggests study

In surgery, it is common for patients to experience intraoperative hypotension, with up to 87% of patients experiencing at least one instance of low mean arterial pressure (less than 65 mmHg). This hypotension can result in serious complications including delirium, acute kidney injury, myocardial ischaemia, and stroke. Thus, it is crucial to prevent and promptly address intraoperative hypotension to enhance perioperative outcomes for surgical patients. Recent systematic review and meta-analysis aimed to evaluate the effect of using the hypotension prediction index (HPI) on various measures of intraoperative hypotension, including time-weighted average (TWA), area under the hypotension threshold (AUHT), incidence, and duration. The review included 8 randomized controlled trials (RCTs) with a total of 613 patients. The key findings are: 1. TWA of hypotension during surgery was significantly lower in the HPI group compared to the control group (mean difference (MD) = -0.19 mmHg, 95% CI: -0.31, -0.08, p=0.001). 2. AUHT was also significantly lower in the HPI group compared to control (MD = -65.03 mmHg x min, 95% CI: -105.47, -24.59, p=0.002). 3. The incidence of hypotension was significantly lower in the HPI group compared to control (risk ratio = 0.83, 95% CI: 0.7, 0.99, p=0.04). 4. The total duration of hypotension was significantly shorter in the HPI group versus control (MD = -12.07 min, 95% CI: -17.49, -6.66, p<0.001). 5. Hypotension duration as a percentage of total surgery time was also significantly lower in the HPI group (MD = -6.30%, 95% CI: -10.23, -2.38, p=0.002).

Conclusion

The authors conclude that the available evidence supports the role of HPI in minimizing various measures of intraoperative hypotension. However, the certainty of evidence was low to moderate for the studied outcomes. The authors note limitations including high heterogeneity between studies, potential publication bias, small sample sizes, and conflicts of interest in most studies. Overall, this meta-analysis provides support for the use of HPI to reduce intraoperative hypotension, but further well-designed RCTs are needed to confirm these findings.

Key Points

1. The time-weighted average (TWA) of hypotension during surgery was significantly lower in the group using the hypotension prediction index (HPI) compared to the control group.

2. The area under the hypotension threshold (AUHT) was also significantly lower in the HPI group compared to the control group.

3. The incidence of hypotension was significantly lower in the HPI group compared to the control group.

4. The total duration of hypotension was significantly shorter in the HPI group compared to the control group.

5. The duration of hypotension as a percentage of total surgery time was significantly lower in the HPI group.

6. The authors conclude that the available evidence supports the use of HPI in minimizing various measures of intraoperative hypotension, but the certainty of evidence was low to moderate and further well-designed studies are needed to confirm these findings.

Reference –

Sriganesh K, Francis T, Mishra RK, Prasad NN, Chakrabarti D. Hypotension prediction index for minimising intraoperative hypotension: A systematic review and meta‑analysis of randomised controlled trials. Indian J Anaesth 2024;68:942‑50.