Clinical trial NCT04217226: Perfusion Index-derived Parameters as Predictors Post-induction Hypotension.
Official title: Evaluation of Perfusion Index-derived Parameters as Predictors of Hypotension After Induction of General Anaesthesia: a Prospective Cohort Study.
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Hypotension
General Anesthesia Induced Hypotension
Lead sponsor: Cairo University
Sponsor class: OTHER
First posted: 2020-01-03
Enrollment: 93
Sex: ALL
Minimum age (years): 18
Maximum age (years): 59
Standard ages: ADULT
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Participants will be adult patients (above 18 years), ASA I-II-III, scheduled for elective surgeries under general anaesthesia.

Brief summary: The perfusion index (PI) is a numerical value for the ratio between pulsatile and non-pulsatile blood flow measured by a special pulse oximeter. PI represents the baseline sympathetic tone which is assumed one of the factors contributing for hypotension. Patients with low PI were reported by Mahendale and Rajasekhar to show greater hypotension after induction of anesthesia. This was explained by the high sympathetic tone in these patients which is suddenly masked by propofol administration leading to profound hypotension.

This study aims to evaluate the ability of preoperative plethysmographic variability index, perfusion index and the Dicrotic Plethysmography to predict post-induction hypotension.

Detailed description: The perfusion index (PI) is a numerical value for the ratio between pulsatile and non-pulsatile blood flow measured by a special pulse oximeter. PI represents the baseline sympathetic tone which is assumed one of the factors contributing for hypotension. Patients with low PI were reported by Mahendale and Rajasekhar to show greater hypotension after induction of anesthesia. This was explained by the high sympathetic tone in these patients which is suddenly masked by propofol administration leading to profound hypotension. Moreover, The PI has been described as a reliable tool for vascular tone assessment and monitoring.

Dicrotic Plethysmography (Dicpleth): is easily derived from the photoplethysmographic signal. It represents the relative height of the dicrotic wave compared with the maximum peak of the waveform, has been described as the amount of reflected wave, dependent on the vascular tone. M.Coutrot et al quantified Dicpleth variations to detect arterial hypotension and mentioned that Dicpleth and PI are both related to vascular tone and are easily derived from the photoplethysmographic signal. Moreover, Chowienczyk PJ et. al. demonstrated that the reduction in Dicpleth is related to the reduction of vascular tone caused by vasodilator drugs, such as salbutamol or glyceryl trinitrate

Eligibility criteria: Inclusion Criteria:

* • Adult patients (18-59 years)

  * ASA I-II
  * Patients scheduled for elective surgeries under general anaesthesia

Exclusion Criteria:

* • Operations which will last for less than 15 minutes.

  * Patients with cardiac morbidities (impaired contractility with ejection fraction \< 40% and tight valvular lesions, unstable angina).
  * Patients with heart block and arrhythmia (atrial fibrillation and frequent ventricular or supraventricular premature beat).
  * Patient with decompansted respiratory disease (poor functional capacity, generalized wheezes, peripheral O2 saturation \< 90% on room air).
  * Patients with peripheral vascular disease or long standing DM affecting PVI readings.
  * Pregnancy.

Primary outcomes:
measure: The area under receiver operating characteristic (AUROC) curve for perfusion index to predict hypotension after induction of anesthesia
timeFrame: 10 minutes
Secondary outcomes:
measure: Mean arterial blood pressure
timeFrame: 15 minutes
measure: Plethysmographic variability index
timeFrame: 10 minutes
measure: Dicrotic Plethysmography
timeFrame: 10 minutes
measure: Incidence of post-induction hypotension
timeFrame: 15 minutes after induction of anesthesia
measure: Heart rate
timeFrame: 5 minutes
measure: systolic arterial blood pressure
timeFrame: 5 minutes
measure: diastolic arterial blood pressure
timeFrame: 5 minutes
Other outcomes:
Locations:
city: Cairo
country: Egypt
facility: Anesthesia Department
Study officials:
affiliation: Cairo University
name: Bassant abdelhamid, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Tsuchiya M, Yamada T, Asada A. Pleth variability index predicts hypotension during anesthesia induction. Acta Anaesthesiol Scand. 2010 May;54(5):596-602. doi: 10.1111/j.1399-6576.2010.02225.x. Epub 2010 Mar 10.
citation: Mehandale SG, Rajasekhar P. Perfusion index as a predictor of hypotension following propofol induction - A prospective observational study. Indian J Anaesth. 2017 Dec;61(12):990-995. doi: 10.4103/ija.IJA_352_17.
citation: Abdelhamid B, Yassin A, Ahmed A, Amin S, Abougabal A. Perfusion index-derived parameters as predictors of hypotension after induction of general anaesthesia: a prospective cohort study. Anaesthesiol Intensive Ther. 2022;54(1):34-41. doi: 10.5114/ait.2022.113956.