External validation of PRAM score for predicting post spinal hypotension during cesarean delivery: A prospective observational study.

BACKGROUND

Recommended prophylaxis against postspinal hypotension includes vasopressor infusions needing continuous and accurate titration preferably with infusion pumps, along with close blood pressure monitoring. In resource constrained settings with high volume obstetric care such intensive management may be difficult for every patient. Thus a dependent, simple tool without need of advanced technology to predict postspinal hypotension is desirable. Although PRAM score is such a tool it has never been validated.

AIM: To validate previously formulated bed-side PRAM score (also after adding postspinal tachycardia as a variable) for predicting postspinal hypotension.

MATERIALS AND

METHODS

This prospective study included 371 consenting patients scheduled for elective/emergency cesarean delivery using standardized spinal block. Postspinal hypotension was defined as systolic blood pressure <80% of baseline or <90mmHg, whichever was higher (upto 15 minutes after baby delivery); and managed with boluses of phenylephrine (50 μg i.v.) till resolution. PRAM score included grade of 1 for each of: baseline heart rate >90 bpm, mean arterial pressure <90 mmHg and age >25 years minutes. Postspinal tachycardia was an increase in heart rate by >10 bpm within 5 minutes.

RESULTS

Incidence of postspinal hypotension was 49.3%, with median onset time of 3 minutes, number of hypotensive episodes ranging from 0 to 5, and amount of phenylephrine required 50-300 μg. ROC analysis showed significant predictive value of PRAM score for postspinal hypotension, with an AUC of 0.578 [95% CI: 0.520-0.636] (P= 0.008); and sensitivity of 89% at cut-off value of PRAM score= 1. When including tachycardia within the first 5 minutes post-block, modified PRAM score had improved predictive accuracy with AUC of 0.601 [95% CI: 0.544-0.659] (P = 0.001).

CONCLUSION

The PRAM score effectively predicts postspinal hypotension during cesarean delivery.