Asymptomatic pneumomediastinum resulting from air in the epidural space -a case report-

Hemodynamic instability caused by pneumorrachis and pneumomediastinum following epidural analgesia: a case report

BACKGROUND

Pneumomediastinum and pneumorrachis are rare complications following epidural analgesia, that can either be asymptomatic or rarely can produce mild to moderate severity symptoms. Most reported cases regarding the presentation of these two entities with epidural analgesia concern asymptomatic patients, however there are cases reporting post-dural puncture headache and respiratory manifestations.

CASE PRESENTATION

We present a case where a combined lumbar epidural and spinal anesthesia was performed using the loss of resistance to air technique (LOR), on a 78-year-old Greek (Caucasian) male undergoing a total hip replacement. Despite being hemodynamically stable throughout the operation, two hours following epidural analgesia the patient manifested a sudden drop in blood pressure and heart rate that required the administration of adrenaline to counter. Pneumomediastinum, pneumorrachis and paravertebral soft tissue emphysema were demonstrated in a Computed Tomography scan. We believe that injected air from the epidural space and surrounding tissues slowly moved towards the mediastinum, stimulating the para-aortic ganglia causing parasympathetic stimulation and therefore hypotension and bradycardia.

CONCLUSION

Anesthesiologists should be aware that epidural analgesia using the LOR to technique injecting air could produce a pneumomediastinum and pneumorrachis, which in turn could produce hemodynamic instability via parasympathetic stimulation.

Pneumomediastinum: A Rare Complication of Epidural Analgesia

Pneumomediastinum is a rare complication following epidural block using the loss of resistance (LOR) technique with air. It is speculated to result from the opening of potential space connecting the epidural space and the posterior mediastinum via intervertebral foramina through fascial planes. To date, only two cases of pneumomediastinum after epidural block have been reported. An incidental finding of pneumomediastinum two days after the procedure has not been reported before. Epidural block as a cause should be considered among multiple causes while interpreting the imaging of this life-threatening complication in the postoperative period.

Pneumorrhachis and pneumothorax after epidural analgesia: A case report and review

Epidural analgesia or anesthesia is a common procedure for pain relief, especially in obstetrics. Pneumorrhachis and pneumothorax are rare complications of epidural analgesia. They are considered asymptomatic entities but have recently caused increased morbidity and mortality. As the use of epidural analgesia and anesthesia increased significantly in the last decade, clinicians must be aware of this entity. This is a case report of pneumorrhachis causing pneumothorax and pneumomediastinum leading to respiratory distress. Case: A 26-year-old obese primigravida at 37 weeks' gestation and with failure of progression of labor underwent lower segment cesarean section under epidural anesthesia. The procedure including the delivery of fetus was uneventful. In the post-anesthesia care unit, the patient became tachypneic, and her oxygen saturation was low despite supplemented oxygen by face mask and adequate analgesia. She was afebrile and was admitted to the surgical intensive care unit (SICU) for further management. In the SICU, incentive spirometry was initiated, and analgesia with intravenous fentanyl was given. Her echocardiogram was normal. Computer tomographic examination ruled out pulmonary embolism but showed pneumorrhachis with extension into the mediastinum and right apical pneumothorax. She was hemodynamically stable. In the next two days, her tachypnea settled, and the oxygen saturation improved to normal. On the third day, she was transferred to the ward and discharged home from there. She was followed up in the outpatient clinic after one and four weeks and was doing well, and her repeat imaging studies were normal. Conclusion: Epidural analgesia can lead to pneumorrhachis and can cause pneumothorax leading to respiratory distress.

A peculiar case of asymptomatic spontaneous pneumomediastinum

OBJECTIVE

To present a case of asymptomatic spontaneous pneumomediastinum and review available evidence-based workup and management.

CASE PRESENTATION

A young Caucasian adult male with a history of inhalational drug use was admitted to the internal medicine service for evaluation of dehydration and mild rhabdomyolysis. Patient had been on the run from the police and had spent the last days prior to presentation without food, water, or shelter. On admission, patient had no complaints, except for thirst. It was detected on physical exam and chest x-ray that patient had subcutaneous emphysema and pneumomediastinum. The patient was treated conservatively and discharged after a period of observation.

CONCLUSION

Spontaneous pneumomediastinum is benign and seen primarily in young adults. It is more commonly associated with symptoms like chest pain and/or dyspnea, making an asymptomatic case particularly distinctive. The etiologies and precipitating factors are varied and often an apparent cause isn't identified. The diagnostic approach involves chest x-ray and/or computed tomography (CT) chest with further workup being largely unnecessary. The tenants of management include bedrest, analgesics, and supplemental oxygen as needed.

Method to Reduce the False-Positive Rate of Loss of Resistance in the Cervical Epidural Region

Background. The cervical epidural space can be detected by the loss of resistance (LOR) technique which is commonly performed using air. However, this technique using air has been associated with a high false-positive LOR rate during cervical interlaminar epidural steroid injections (CIESIs). Objective. We investigated whether the detection of LOR with contrast medium might reduce the false-positive LOR rate on the first attempt. Methods. We obtained data retrospectively. A total of 79 patients were divided into two groups according to the LOR technique. Groups 1 and 2 patients underwent CIESI with the LOR technique using air or contrast medium. During the procedure, the injection technique (median or paramedian approach), final depth, LOR technique (air or contrast), total number of LOR attempts, and any side effects were recorded. Results. The mean values for the total number of LOR attempts were 1.38 ± 0.65 (Group 1) and 1.07 ± 0.25 (Group 2). The false-positive rate on the first attempt was 29.4% and 6.6% in Groups 1 and 2, respectively (P = 0.012). Conclusions. The use of contrast medium for LOR technique is associated with a lower rate of false-positivity compared with the use of air.