• Published
    06-03-2024
  • Issue
    Vol: 28 Issue: 01, 2024
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A STUDY TO ASSESS THE BASELINE PULSE OXIMETER PERFUSION INDEX AS A PREDICTOR OF INTRAOPERATIVE HYPOTENSION IN PARTURIENTS UNDERGOING SPINAL ANAESTHESIA FOR CAESAREAN SECTION

  • Dr Darshini S, Dr Vyshnavi Sriram, Tulika Vinaik , *Dr. Ashwini N

Keywords: Perfusion Index, Caesarean Section, Post Spinal Hypotension

ABSTRACT:-
Introduction: Hypotension following Spinal Anaesthesia (SA) in Lower Segment Caesarean Section (LSCS) can be deleterious to the parturient and to the fetus. Perfusion index (PI) is the ratio of pulsatile blood flow to non-pulsatile blood flow in the peripheral vascular tissue which can be measured using a pulse oximeter based on the amount of infrared light absorbed. PI can assess perfusion dynamics and detect the likelihood of development of hypotension following SA. Hence, pulse-oximeter derived PI can be used as a non-invasive means to predict intra-operative hypotension and take adequate measures to prevent it. Aims & Objectives: To evaluate baseline perfusion index of greater than 3.5 (>3.5) as a predictor of intraoperative hypotension following spinal anaesthesia in lower segment caesarean section. Methodology: Sixty American Society of Anaesthesiologists Physical status (ASA-PS) class II parturients undergoing elective LSCS under SA were selected for a prospective comparative study after approval from Institutional Ethical Committee and informed consent. Baseline hemodynamic values including PI were recorded in supine position with wedge under right buttock to prevent aorto-caval compression. Parturients were divided into two groups. Parturients with baseline PI 3.5 were assigned to Group1 and those with PI ≥3.5 to Group2. A fall in >20% of systolic blood pressure (SBP) or SBP 90 mmHg after SA was treated with IV bolus Inj.ephedrine (6mg). The number of incidences of hypotension and doses of ephedrine required were recorded in both groups for 60 minutes following SA. Results: The demographic parameters were statistically similar in both the groups. Our study showed statistically significant increase in the incidence of hypotension and higher use of intravenous ephedrine 6 mg bolus doses in Group 2 (PI ≥3.5) compared to Group 1 (PI3.5) after SA. There were 30 parturients in each group. 24 parturients in Group 2 developed hypotension compared to 8 parturients in Group 1 with Mean Total Amount of Ephedrine used in Group 1 being 2.4 ± 4.34 mg and in Group 2 being 12.6 ± 8.54 mg (p = 0.001). We also found out a new cut-off PI of 3.8. There was no statistically significant difference in APGAR score between the two groups. Conclusion: Higher baseline PI is associated with higher incidence of hypotension following SA in parturients undergoing LSCS. Hence, PI can be used as a tool in predicting intraoperative hypotension in parturients undergoing elective LSCS and help in preventing it.