Case Presentation
A 19-year-old primigravida woman presented to the antenatal unit at 40 weeks for labour induction by choice. She had a healthy pregnancy, attended regular check-ups, and wasn’t on any medications. On presentation, she didn’t have any complaints, and her vital signs were all normal. During the physical exam, the doctors noted that her uterus was the appropriate size for her stage of pregnancy. They used misoprostol and oxytocin to induce labour.
Headache Caused by Analgesia
When the woman reached around 3 centimetres of cervical dilatation, she requested epidural analgesia to manage her labour pain. The doctors performed an epidural puncture in her lower back while she was sitting. They monitored her during the procedure using blood pressure monitoring, pulse oximetry, and cardiac monitoring. She experienced tachycardia after the injection, but it spontaneously went back to normal. Once the doctors had placed the epidural successfully, they gave her analgesia with Fentanyl as needed. Eight hours after the doctors inserted the epidural catheter, she started experiencing a severe headache at the front of her head and pain in her neck. She described the headache and neck pain as very intense, throbbing, and worsening on moving her head or neck. She didn’t have any visual problems, sensitivity to light, nausea, or weakness in her limbs. Her vital signs remained normal, and a neurological examination didn’t reveal any abnormalities. The doctors considered several possibilities for the cause of her new-onset headache and neck pain after the difficult epidural puncture. Such as accidental puncture of the subarachnoid space causing a loss of cerebrospinal fluid, post-dural puncture headache, and pneumocephalus. Despite the headaches and neck pain, the epidural analgesia effectively managed her labour pain, so the doctors continued it. They closely monitored her and with time the severity of the headache improved.
As the first stage of labour didn’t progress, doctors made the decision to perform a Cesarean section. Even after the surgery, she complained of a persistent headache.
Post-operative follow-up
On the first post-operative day, the anaesthetic team advised a head and neck computed tomography (CT) scan as the patient was still experiencing positional headaches. The CT scan revealed the presence of air in the brain cavities, specifically in the frontal part of the lateral ventricles, as well as in the suprasellar and peri mesencephalic cisterns. However, it didn’t cause any significant pressure on the brain or displacement. There was no sign of bleeding or stroke. The CT scan of the neck showed air in the spinal canal, mainly in the upper back and neck area. The patient continued to receive regular follow-up care from the anaesthetic team. They closely monitored her condition and managed her pain conservatively with appropriate medication.
On the second day after the Cesarean section, she reported feeling better, and her headache had improved. She was able to walk without any difficulty, and her headache and neck pain didn’t get worse. Thus, doctors discharged her from the hospital on the third day with instructions to return if she experienced any adverse symptoms.
Complications
Initially, she found relief from her headaches with the pain medication she was given. However, two days after being discharged, she returned to the hospital because she had frontal headaches. They were extremely severe, despite taking acetaminophen and oxycodone for pain. She complained that the pain spread to her neck and both arms, causing numbness and tingling sensations in her arms on both sides. During this visit, her vital signs were stable. She didn’t have a fever, and her oxygen levels were normal when breathing room air. The physical examination showed a well-healed Cesarean scar without any bleeding or discharge. There were no signs of muscle weakness or sensory problems. Another CT scan of her head revealed a decrease in the amount of air in the brain ventricles and left peri mesencephalic cistern. The repeat CT scan of her neck showed a decrease in the amount of air in the upper back and neck epidural space compared to the previous scan. The anaesthesia and neurosurgery teams were consulted for further evaluation and management. She received conservative treatment, which included pain relief with a combination of butalbital, acetaminophen, and caffeine. Moreover, doctors administered intravenous fluids to keep her hydrated, rest, and caffeine during the day when she was active. Initially, doctors did not consider a blood patch because there were concerns that increased pressure in the epidural space might make her symptoms worse. Over the next two days, her headaches and neck pain gradually resolved, and she was discharged home.
What is Pneumocephalus?
Pneumocephalus, also known as intracranial air, is a condition in which air is present in the intracranial space. It is usually seen after head injuries, cranial surgeries, or infections. In rare cases, it can occur as a complication of spinal or epidural punctures when air accidentally enters the subdural or subarachnoid space.
There are different theories about how pneumocephalus develops after an accidental dural puncture. One theory suggests that air enters the skull through a defect in the dural membrane and acts as a one-way valve. This prevents the air from flowing back out. Another theory suggests that the leakage of cerebrospinal fluid caused by the puncture creates negative pressure. This pulls air into the intracranial space.
Pneumocephalus can be classified as acute or delayed, depending on whether it occurs within 72 hours or more than 72 hours after the dural puncture.
The most common symptom of pneumocephalus is headache, typically felt in the frontal or occipital regions. The headache worsens with an upright position and movement, similar to post-dural puncture headache (PDPH), which is a common headache after epidural or spinal punctures. Nausea, vomiting, neck pain or stiffness, changes in vision, and cranial nerve deficits can also occur.
Doctors commonly use non-contrast head CT scans to diagnose pneumocephalus because they can detect even small amounts of air.
The treatment of pneumocephalus depends on its severity. In most cases of simple pneumocephalus, no specific intervention is needed as the air is gradually absorbed by the body over a few weeks. Conservative management involves providing simple pain relief and administering oxygen in a supine or lying position to enhance air absorption. However, tension pneumocephalus requires immediate surgical intervention to remove the accumulated air.
Conclusion
In conclusion, pneumocephalus is a very rare complication of spinal or epidural procedures. It is important to be cautious during the procedure and also in the post-procedure period when symptoms of complications may arise. While most cases can be managed without surgery, a thorough evaluation is necessary to identify cases of tension pneumocephalus that require immediate neurosurgical intervention.
