Elie Kantor1, Philippe Montravers, Dan Longrois, Jean Guglielminotti. 1. From the Département d'Anesthésie-Réanimation, Hôpital Bichat, AP-HP (EK, PM, DL, JG), Université Paris Diderot, Sorbonne Paris Cité (PM, DL, JG) and INSERM, UMR 738 (JG), Paris, France.
Abstract
BACKGROUND: Patients assess their own pain with a numerical rating scale (NRS). In the postanaesthesia care unit (PACU), NRS helps to determine and monitor analgesic administration, but is useless in patients who are unable to communicate. In non-PACU patients, acute pain increases pupillary diameter and pupillary light reflex amplitude (PLRA), the difference between pupillary diameter before and after light stimulation. OBJECTIVES: To study the association between postoperative pain (NRS) and pupillary diameter or PLRA in PACU patients after routine anaesthetic care. DESIGN: Cross-sectional cohort study. SETTING: Bichat-Claude Bernard Hospital, Paris. PATIENTS: One hundred and forty-five patients undergoing planned surgery under general anaesthesia. INTERVENTIONS: NRS, pupillary diameter and PLRA were measured on arrival in the PACU. When NRS was more than 4, intravenous morphine titration was started and a second measurement performed. MAIN OUTCOME MEASURES: Association between NRS and pupillary diameter or PLRA was assessed with Pearson correlation coefficient (r) as was association between changes in these variables after morphine titration. RESULTS: Mean NRS was 4.7, and was more than 4 in 79 patients (55%). No statistically significant association was observed between NRS and pupillary diameter (r = 0.10, P = 0.54) or PLRA (r = 0.03, P = 0.72). Twenty-seven patients (19%) received morphine titration with significant decreases in NRS, pupillary diameter and PLRA afterwards. No association was observed between NRS changes and pupillary diameter or PLRA changes. CONCLUSION: Acute postoperative pain is not associated with pupillary diameter or PLRA. Further research is required to develop tools to assess pain in the PACU.
BACKGROUND:Patients assess their own pain with a numerical rating scale (NRS). In the postanaesthesia care unit (PACU), NRS helps to determine and monitor analgesic administration, but is useless in patients who are unable to communicate. In non-PACUpatients, acute pain increases pupillary diameter and pupillary light reflex amplitude (PLRA), the difference between pupillary diameter before and after light stimulation. OBJECTIVES: To study the association between postoperative pain (NRS) and pupillary diameter or PLRA in PACUpatients after routine anaesthetic care. DESIGN: Cross-sectional cohort study. SETTING: Bichat-Claude Bernard Hospital, Paris. PATIENTS: One hundred and forty-five patients undergoing planned surgery under general anaesthesia. INTERVENTIONS: NRS, pupillary diameter and PLRA were measured on arrival in the PACU. When NRS was more than 4, intravenous morphine titration was started and a second measurement performed. MAIN OUTCOME MEASURES: Association between NRS and pupillary diameter or PLRA was assessed with Pearson correlation coefficient (r) as was association between changes in these variables after morphine titration. RESULTS: Mean NRS was 4.7, and was more than 4 in 79 patients (55%). No statistically significant association was observed between NRS and pupillary diameter (r = 0.10, P = 0.54) or PLRA (r = 0.03, P = 0.72). Twenty-seven patients (19%) received morphine titration with significant decreases in NRS, pupillary diameter and PLRA afterwards. No association was observed between NRS changes and pupillary diameter or PLRA changes. CONCLUSION: Acute postoperative pain is not associated with pupillary diameter or PLRA. Further research is required to develop tools to assess pain in the PACU.
Authors: Eric Yang; Matthias Kreuzer; September Hesse; Paran Davari; Simon C Lee; Paul S García Journal: J Clin Monit Comput Date: 2017-03-08 Impact factor: 2.502
Authors: Giulia Liberati; Maxime Algoet; Anne Klöcker; Susana Ferrao Santos; Jose Geraldo Ribeiro-Vaz; Christian Raftopoulos; André Mouraux Journal: Sci Rep Date: 2018-05-29 Impact factor: 4.379