(405) What is the Effect on Acute Pain when a Patient's Sleep is Disturbed by Opioid-Induced Nausea and Vomiting (OINV)?

Abstract

Sleep is an important factor in postoperative recovery, especially for patients experiencing moderate-to-severe acute pain. In contrast, sleep disturbance may have deleterious effects on patient recovery, including increased pain and length-of-stay.1 However, it is unclear if nausea and vomiting interfere with sleep and with what analgesic consequence. Is there evidence of OINV-related sleep disturbance and its effect on acute pain in a randomized controlled trial (RCT)? In a previous RCT,2 it was noted that some patients using hydrocodone 7.5mg/acetaminophen 325mg (HC/APAP) awoke with nausea, retching and/or vomiting, requesting antiemetic therapy. In the current RCT,3 therefore, patients were observed while asleep so that emetic symptoms and pain could be documented if they awoke. Following first metatarsal bunionectomy, patients with moderate or severe pain on a categorical pain intensity scale and a 0-to-10 pain intensity scale (PI-NRS) were randomly assigned to take HC/APAP or placebo under double-blind conditions every 4-6 hours. Patients were monitored regularly as in-patients over 48 hours, including, in particular, during periods of sleeping between 9 pm and 7 am: if patients awoke from sleep, episodes of retching, vomiting and other adverse events were documented if present and patients rated nausea intensity on a 0-to-10 Likert scale and pain intensity on the PI-NRS. Of 113 HC/APAP-treated patients who developed OINV over the 48-hour treatment period, 29 patients (26%) awoke from sleep complaining of moderate-to-severe nausea, retching or vomiting, requesting an antiemetic. Compared to the summed pain intensity differences (SPID48) of these patients with OINV-related sleep disturbance (63.2), SPID48 values were 108% higher for the 137 HC/APAP-treated patients without OINV-related sleep disturbance (131.1, p<0.001). We conclude that OINV causes sleep disturbance, interfering with pain reduction and contributing to less effective pain relief. Future research should examine the effect of sleep disturbance of any etiology on pain control. Sleep is an important factor in postoperative recovery, especially for patients experiencing moderate-to-severe acute pain. In contrast, sleep disturbance may have deleterious effects on patient recovery, including increased pain and length-of-stay.1 However, it is unclear if nausea and vomiting interfere with sleep and with what analgesic consequence. Is there evidence of OINV-related sleep disturbance and its effect on acute pain in a randomized controlled trial (RCT)? In a previous RCT,2 it was noted that some patients using hydrocodone 7.5mg/acetaminophen 325mg (HC/APAP) awoke with nausea, retching and/or vomiting, requesting antiemetic therapy. In the current RCT,3 therefore, patients were observed while asleep so that emetic symptoms and pain could be documented if they awoke. Following first metatarsal bunionectomy, patients with moderate or severe pain on a categorical pain intensity scale and a 0-to-10 pain intensity scale (PI-NRS) were randomly assigned to take HC/APAP or placebo under double-blind conditions every 4-6 hours. Patients were monitored regularly as in-patients over 48 hours, including, in particular, during periods of sleeping between 9 pm and 7 am: if patients awoke from sleep, episodes of retching, vomiting and other adverse events were documented if present and patients rated nausea intensity on a 0-to-10 Likert scale and pain intensity on the PI-NRS. Of 113 HC/APAP-treated patients who developed OINV over the 48-hour treatment period, 29 patients (26%) awoke from sleep complaining of moderate-to-severe nausea, retching or vomiting, requesting an antiemetic. Compared to the summed pain intensity differences (SPID48) of these patients with OINV-related sleep disturbance (63.2), SPID48 values were 108% higher for the 137 HC/APAP-treated patients without OINV-related sleep disturbance (131.1, p<0.001). We conclude that OINV causes sleep disturbance, interfering with pain reduction and contributing to less effective pain relief. Future research should examine the effect of sleep disturbance of any etiology on pain control.