Postoperative Effects of Intraoperative Temporary Phrenic Nerve Paralysis in Lung Resection Surgery (PNCrush)

Postoperative Effects of Phrenic Nerve Paralysis Induced During Resection Surgery: A Prospective Study With Electromyography

This prospective clinical study aimed to evaluate the postoperative effects of temporary phrenic nerve paralysis induced by intraoperative phrenic nerve crush during lung resection surgery. The study compared postoperative pulmonary function, diaphragm activity, and clinical outcomes between patients who underwent intraoperative phrenic nerve crush and those who did not. The objective was to assess the reversibility, safety, and clinical impact of temporary phrenic nerve paralysis in relation to postoperative residual pleural space and prolonged air leak.

Study Overview

• Status: Completed
• Conditions: Prolonged Air Leak; EMG; Phrenic Nerve
• Intervention / Treatment: Procedure: İntraoperative phrenic nerve compression

Detailed Description

This prospective observational study was conducted at the University of Health Sciences, Konya City Hospital, Department of Thoracic Surgery, between September 2019 and March 2023. The study included patients who underwent lung resection surgery via muscle-sparing thoracotomy. In the intervention group, a controlled intraoperative phrenic nerve crush was applied to induce temporary phrenic nerve paralysis. In the control group, no phrenic nerve manipulation was performed.

The primary objective was to evaluate the postoperative effects and reversibility of temporary phrenic nerve paralysis using diaphragm electromyography (EMG) and pulmonary function tests (FEV1, FVC). Secondary objectives included the assessment of residual pleural space filling, prolonged air leak, chest tube duration, and length of hospital stay. The study also aimed to determine whether temporary phrenic nerve paralysis could help minimize postoperative residual pleural space and prolonged air leak without causing permanent functional impairment.

Ethical approval for the study was obtained from the Necmettin Erbakan University Faculty of Medicine Ethics Committee (approval number: NEU2019-1421). Written informed consent was obtained from all participants prior to enrollment.

• Study Type: Interventional
• Enrollment (Actual): 55
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Konya
    • Konya, Konya, Turkey (Türkiye), 42080
      • Konya City Hospital, Department of Thoracic Surgery

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients (18+) who underwent lobectomy via muscle sparing thoracotomy

  • Patients with adequate preoperative pulmonary function to tolerate lobectomy
  • Patients who provided written informed consent for participation.
  • Patients with available postoperative follow-up data, including EMG and pulmonary function tests

Exclusion Criteria:

• Patients who underwent wedge resection, segmentectomy, pneumonectomy, or VATS procedures
• Patients with previous phrenic nerve injury, diaphragmatic paralysis, or neuromuscular disorders affecting respiratory muscles.
• Patients with incomplete postoperative follow-up or missing EMG/PFT data

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Phrenic crush; Patients underwent standard lobectomy via muscle-sparing thoracotomy with brief intraoperative compression (1-2 seconds) of the phrenic nerve to induce transient diaphragmatic paralysis.	Procedure: İntraoperative phrenic nerve compression; Temporary intraoperative compression (1-2 seconds) of the phrenic nerve during lobectomy to induce transient diaphragmatic paralysis and minimize postoperative residual space.
No Intervention: Control; Patients underwent standard lobectomy via muscle-sparing thoracotomy without any intraoperative manipulation or compression of the phrenic nerve.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diaphragmatic Electromyography	Quantitative assesment of diaphragmatic muscle activity using preoperative and postoperative EMG, recorded as motor unit action potential amplitude (mA) and duration (ms), to evaluate the degree of diaphragmatic dysfunction or recovery following intraoperative phrenic nerve compression.	Preoperative; 3 weeks postoperative; 6 months postoperative
Pulmonary Function Test - FEV1	Spirometric assessment of forced expiratory volume in 1 second (FEV1) to evaluate postoperative respiratory performance and the potential impact of brief intraoperative phrenic nerve compression. FEV1 values will be recorded as absolute volume (L) and as percent predicted (% predicted). Comparisons will be made between groups at each time point.	Preoperative; 3 weeks postoperative; 6 months postoperative
Pulmonary Function Test - FVC	Spirometric assessment of forced vital capacity (FVC) to evaluate postoperative respiratory performance and the potential impact of brief intraoperative phrenic nerve compression. FVC values will be recorded as absolute volume (L) and as percent predicted (% predicted). Comparisons will be made between groups at each time point.	Preoperative; 3 weeks postoperative; 6 months postoperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Chest Tube Duration	Duration of chest tube placement recorded as the number of postoperative days from the time of insertion until removal. Comparisons will be made between groups.	Up to postoperative day 30
Length of Hospital Stay	Total duration of hospitalization recorded as the number of days from the day of surgery until discharge. Comparisons will be made between groups.	Up to postoperative day 30
Prolonged Air Leak	Incidence of prolonged postoperative air leak, defined as an air leak lasting more than 5 days after surgery. The outcome will be recorded as the number of participants with and without prolonged air leak in each group.	Up to postoperative day 30

Collaborators and Investigators

• Sponsor: Ferdane Melike Duran
• Investigators: Principal Investigator: Ferdane M Duran, MD, University of Health Science, Konya City Hospital

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2019
• Primary Completion (Actual): March 31, 2023
• Study Completion (Actual): June 30, 2023

Study Registration Dates

• First Submitted: November 17, 2025
• First Submitted That Met QC Criteria: November 21, 2025
• First Posted (Actual): December 2, 2025

Study Record Updates

• Last Update Posted (Actual): December 2, 2025
• Last Update Submitted That Met QC Criteria: November 21, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: prolonged air leak; residual air space; Phrenic nerve crush; Diaphragm electromyography
• Other Study ID Numbers: NEU2019-1421 (Other Identifier: Necmettin Erbakan University Faculty of Medicine Ethics Commitee)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: İndividual participant data will not be shared because the study includes patient-specific clinical and electrophysiological data that cannot be fully anonymized. Data will only be used for the analysis described in the approved protocol.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No