The role of “Integrated Pulmonary Index” monitoring during morphine-based intravenous patient-controlled analgesia administration following supratentorial craniotomies: a prospective, randomized, double-blind controlled study

Abstract

Objective: Morphine is commonly used in post-operative analgesia, but opioid-related respiratory depression causes a general reluctance for its use. The “Integrated Pulmonary Index” is a tool calculated from non-invasively obtained respiratory and hemodynamic parameters. The aim of this prospective, randomized, double blind, and placebo-controlled study is to determine a more safe and effective dose for morphine in patient-controlled analgesia following supratentorial craniotomy using the “Integrated Pulmonary Index”.

Methods: This study included 60 patients (ASA I, II, and III). All patients used iv PCA for 24 h following supratentorial craniotomy. The PCA was set to administer a bolus dose of 1 mg morphine in Group 1 and 0.5 mg morphine in Group 2. The PCA contained placebo in Group 3 and patients received dexketoprofen 50 mg iv after awakening, repeated every 8 h. The IPI and NRS scores, total morphine consumption, and morphine related side-effects were recorded at 10 min, 1, 2, 6, 12, and 24 h post-operatively. The lowest IPI score, count of apnea, and desaturation events were recorded during the study period.

Results: The IPI scores were similar among the groups. Although a statistically significant difference was not observed among the groups the lowest IPI scores were observed in Group 1; apnea and desaturation counts were also higher in Group 1. Statistically significant differences were not observed among the groups in terms of pain scores, but were lower in Groups 1 and 2 compared to Group 3.

Conclusion: Patient controlled analgesia with 0.5 mg morphine may be safe and effective for pain management following supratentorial craniotomies. Integrated pulmonary index can be used for detecting opioid-induced respiratory depression.

Clinical Trials registration number: NCT02929147.

Keywords:

• Integrated pulmonary index
• Morphine
• Patient controlled analgesia
• Supratentorial craniotomy

Transparency

Declaration of funding

The study has no funding.

Declaration of financial/other relationships

The authors declare that they have no conflict of interest. CMRO peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Acknowledgments

No assistance in the preparation of this article is to be declared.