Fatal posterior fossa pneumocephalus due to hydrogen peroxide irrigation of lumbar wound

Fatal brain stem failure developed suddenly in a 40-year-old male undergoing irrigation of an infected wound consequent to lumbar disc space infection. CT of head revealed posterior fossa pneumacephalus compressing the brain stem, which most likely developed from ingress of nascent oxygen under pressure through a defect in the thecal sac.

Nitrous oxide withdrawal reduces intracranial pressure in the presence of pneumocephalus

Nitrous oxide anesthesia has been implicated as contributing to the development of delayed tension pneumocephalus following surgery performed in the sitting position. The authors tested the hypothesis that withdrawal of nitrous oxide anesthesia administered during formation of an intracranial gas cavity would lead to a decrease in intracranial pressure (ICP) as N2O diffuses from the cavity back into the blood. Ten halothane-anesthetized rabbits were prepared for measurement of supracortical ICP and arterial blood pressure (BP) and for intracranial volume alterations via a cisterna magna infusion catheter. Hyperventilation (Paco2 = 28-30 mmHg) and mannitol were used to shrink the brain to accommodate intracranial infusion of either air or lactated Ringer's (LR) solution, which was used to elevate ICP to between 10-15 mmHg from a baseline ICP of 2.1 +/- 2.5 mmHg over a period of 8 to 10 min. Following stabilization at an elevated ICP, inhalation of nitrous oxide (75%) was either initiated or withdrawn (if already present during the induced ICP increase) and the subsequent changes in mean ICP and BP were recorded. Following ICP elevation with LR to 10 +/- 1 mmHg, initiation of 75% N2O administration resulted in no change in ICP and modest increases (P less than 0.05) in BP and cerebral perfusion pressure (CPP = BP - ICP) after 4 min. However, when ICP was raised (to 12 +/- 3.5 mmHg) with intracranial air infusion, subsequent initiation of 75% N2O inhalation caused an abrupt ICP increase to 22.3 +/- 9 mmHg (from control P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Pneumocephalus induced by bromocriptine treatment in male prolactinoma--a case report]

The authors reported a case of pneumocephalus induced by bromocriptine (Bc) treatment for a recurrent invasive prolactinoma. The patient was a 38-year old man, who had been treated for 12 years, with three times of craniotomies and two times of irradiation therapies. CT scan showed the recurrence of the tumor, which extended into bilateral middle fossa, left orbit and left cerebellopontine angle. Serum prolactin levels elevated to 35,200 ng/ml. Then Bc was administered in a dose of 5 mg/day. Serum PRL concentration fell to 2,090 ng/ml one month after the initiation of the treatment, when he complained of headache, nausea and vomiting. Since these symptoms were considered as the side effects of Bc, the dose was reduced to 2.5 mg/day. Three weeks later, plain craniograms showed marked pneumocephalus, while no tumor was found on CT scan. The administration of Bc was stopped and he was prescribed a complete rest for a month. The air was collected again when he began to walk around. Therefore, the transsphenoidal operation was performed in order to pack the sella turcica and sphenoid sinus with muscle pieces. Since the pneumocephalus could not be cured, the muscle, taken from the thigh, was spread throughout the left middle fossa by the front-temporal craniotomy. When Bc reduces the size of the invasive prolactinomas, the intra- and extra-cranial spaces may be communicated. The greatest care should be taken for pneumocephalus, CSF rhinorrhea and/or meningitis during the Bc treatment of prolactinomas.