Can Right Toe Perfusion Index or Pleth Variability Index Predict Spinal Anesthesia Induced Hypotension?

Kahramanmaraş Sütçü İmam University (KSU)

Status: Completed

Conditions: Hypotension; Cesarean Section Complications; Spinal Anesthesia; Pleth Variability Index; Perfusion Index

Study type: Observational

Funder types: Other

Identifiers

NCT03956186

KSU 2019-07

Details and patient eligibility

About

Spinal anesthesia for caesarean section is associated with a decrease in systemic vascular resistance and cardiac output and may cause hypotension in a significant portion of the parturients. Hypotension during delivery may cause maternal and fetal complications. If parturients who are likely to develop hypotension after spinal anesthesia can be identified before surgery, anesthesiologists would have opportunity to take measures such as prophylactic vasopressor administration. Perfusion index (PI) measured by pulse oximetry reflects vasomotor tone which affects the degree of hypotension after spinal anesthesia. This is a non-invasive method of assessing the relative vascular tone with the use of pulse oximeter which calculates the ratio of pulsatile versus the non-pulsatile component of the blood flow. A lower PI indicates greater peripheral vasomotor tone. Pleth variability index (PVI) is calculated using maximum and minimum values of perfusion index during respiratory cycles. PVI is one of the dynamic indices that can predict fluid responsiveness. There are several studies investigating the predictive value of finger PI and PVI on hypotension after spinal anesthesia. However the aortocaval compression by the gravid uterus directly effects the lower extremity perfusion. So, in this study we aimed to investigate whether the right toe PI and PVI values at supine and left lateral positions can predict hypotension during caesarean section.

Enrollment: 60 patients

Sex: All

Ages: 18 to 45 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• singleton parturient
• planned for elective LSCS under spinal anesthesia

Exclusion criteria

• gestational age < 36 weeks

  • emergency cases
  • placenta previa, pre-eclampsia
  • BMI>40
  • Reynauld disease
  • patient refusal
  • cardiovascular disease

Trial design

60 participants in 2 patient groups

Hypotension group

Description:

Parturients undergoing elective C/S under spinal anesthesia whose systolic arterial pressure drop below 80 mmHg or have symptoms of hypotension such as dizziness, nausea and vomiting during the procedure.

Non-hypotension group

Description:

Parturients undergoing elective C/S under spinal anesthesia whose systolic arterial pressure does not drop below 80 mmHg or have any symptoms of hypotension during the procedure.