Perfusion index as a predictor of hypotension following propofol induction - A prospective observational study

Abstract

Background and Aims:Hypotension during propofol induction is a common problem. Perfusion index (PI), an indicator of systemic vascular resistance, is said to be predictive of hypotension following subarachnoid block. We hypothesised that PI can predict hypotension following propofol induction and a cut-off value beyond which hypotension is more common can be determined.Methods:Fifty adults belonging to the American Society of Anesthesiologists' physical status I/II undergoing elective surgery under general anaesthesia were enrolled for this prospective, observational study. PI, heart rate, blood pressure (BP) and oxygen saturation were recorded every minute from baseline to 10 min following induction of anaesthesia with a titrated dose of propofol, and after endotracheal intubation. Hypotension was defined as fall in systolic BP (SBP) by >30% of baseline or mean arterial pressure (MAP) to <60 mm Hg. Severe hypotension (MAP of <55 mm Hg) was treated.Results:Within first 5-min after induction, the incidence of hypotension with SBP and MAP criteria was 30% and 42%, respectively, and that of severe hypotension, 22%. Baseline PI <1.05 predicted incidence of hypotension at 5 min with sensitivity 93%, specificity 71%, positive predictive value (PPV) 68% and negative predictive value (NPV) 98%. The area under the ROC curve (AUC) was 0.816, 95% confidence interval (0.699–0.933), P < 0.001Conclusion:Perfusion index could predict hypotension following propofol induction, especially before endotracheal intubation, and had a very high negative predictive value.

The use of peripheral perfusion index as a predictor for patient’s response to deliberate hypotension during functional endoscopic sinus surgery. A prospective observational study

“…In line with our findings, Mehandale and Rajasekhar [20] tested the ability of baseline PPI to predict hypotension following propofol induction of general anesthesia in 50 adult healthy patients. The study revealed a significant correlation between the baseline PPI and propofol-induced hypotension.…”

Correlation between the Perfusion Index and Intraoperative Hypothermia: A Prospective Observational Pilot Study

“…The PI is calculated as the ratio of pulsatile to non-pulsatile signals in arterial blood flow [ 6 , 7 ]. To date, the PI has been used to predict low blood pressure [ 8 ], identify early success indicators of central and peripheral nerve blocks [ 9 , 10 ], assess pain [ 11 , 12 , 13 ], evaluate systemic vascular resistance [ 14 , 15 ], indicate the success of sympathectomy for hyperhidrosis [ 16 ], and identify the incidence of hypotension after spinal anesthesia [ 17 ]. However, few studies have investigated the correlation between the PI and body temperature.…”

Ultrasound measurement of inferior vena cava collapsibility as a tool to predict propofol-induced hypotension

“…Propofol is a common cause of hypotension. [ 2 ] There are many studies which have explained the effect of hypotension on various organ systems and their functioning; it can present as stroke,[ 3 ] myocardial injury, or acute kidney injury in patients undergoing general[ 3 ] and cardiac[ 4 ] surgeries. Postinduction hypotension can lead to increased postoperative morbidity and mortality, as well as postoperative stay.…”

“…[ 5 ] However, propofol is known to cause hypotension. [ 1 2 5 6 ] Hypotension following propofol is due to myocardial suppression and decreased systemic vascular resistance. [ 6 ] A multimodal approach consisting of nonpharmacological and pharmacological interventions has been advocated to reduce postinduction hypotension, and assessment of inferior vena cava (IVC) diameter is one of them.…”