Posterior reversible encephalopathy syndrome following an inadvertent dural puncture during an emergency laparotomy for ischemic colitis – a case report
A 62-year-old woman presented acutely with severe sudden onset left-sided abdominal pain and several episodes of diarrhea with blood mixed in with stool. Her past medical history included coeliac disease and hypertension that was well controlled with ramipril 10 mg daily. On admission, observations were: temperature 36.4°C, blood pressure 115/50 mmHg, heart rate 75 bpm, respiratory rate 16, and oxygen saturations of 99% breathing on air. Examination revealed localized peritonitis of the left abdomen, and rectal examination showed altered blood with no stool. A computed tomography (CT) scan of her abdomen and pelvis showed an appearance consistent with colitis involving the transverse and sigmoid colon, the distribution suggesting ischemic colitis. She was initially managed conservatively with analgesia and intravenous antibiotics. Flexible sigmoidoscopy the following day showed an ischemic splenic flexure, and the decision was made for the patient to undergo a laparotomy. Preoperatively, the patient remained normotensive.\nOn the second day of her admission, the patient was taken to theater for a laparotomy. A low thoracic epidural was attempted for postoperative pain relief; however, the procedure was abandoned after one attempt due to a dural tap. Consequently, the patient had general anesthesia with systemic opioid analgesia and a rectus sheath block. Intraoperative findings revealed an ischemic left colon and proximal sigmoid colon; therefore, she underwent a Hartmann’s procedure. Intraoperatively, the patient remained hemodynamically stable, with an average blood pressure of 120/60 mmHg. Postoperatively, the patient was commenced on a morphine patient-controlled analgesia for pain relief and was anti-coagulated for the ischemic colitis. Investigations towards underlying conditions likely to have caused the ischemic colitis were also carried out. Screening for presence of the anti-phospholipid antibody, JAK2 mutation, and thrombophilia proved negative.\nPostoperatively, the patient developed an ileus. This was managed conservatively with nasogastric drainage and intravenous fluids. Her blood pressure rose from an average of 150/80 mmHg on postoperative day 1 to 190/80 mmHg on postoperative day 3, despite remaining on her usual dose of ramipril. On postoperative day 3, the patient complained of a frontal headache and “cloudy vision.” The headache and rising blood pressure was initially thought to be due to postoperative pain and dural tap; on postoperative day 3, she was commenced on a second antihypertensive, amlodipine. On postoperative day 4, headache, severe hypertension, and worsening vision continued. Neurological examination revealed no focal abnormality; however, fundoscopy showed blurred discs but no retinal hemorrhages or exudates. The patient was commenced on bisoprolol and underwent an urgent CT head scan ().\nThe CT head scan revealed bilateral areas of low attenuation in the left occipital lobe and to a lesser extent in the right occipital lobe. There were also some patchy areas of low attenuation in the right and left cerebellar hemispheres. There was neither mass effect nor enhancement.\nA subsequent magnetic resonance imaging scan of the head and magnetic resonance venography () showed patchy white matter edema most markedly in the occipital lobes but extending anteriorly to reach the frontal lobes, consistent with PRES.\nDespite these findings, blood pressure continued to be controlled with oral medication. However, on postoperative day 6, the patient developed status epilepticus. Repeat head CT excluded an intracerebral bleed. The patient was loaded with intravenous phenytoin, intubated, and blood pressure was tightly controlled with a mean arterial pressure of 85 mmHg. The patient was extubated the following day. Blood pressure continued to be tightly controlled with regular antihypertensives, and she remained on phenytoin to prevent further seizures.\nThe patient continued to improve and was discharged 21 days postoperatively with blood pressure controlled (systolic readings of 120–130 mmHg) on her usual dose of ramipril plus 10 mg amlodipine daily. The only residual neurological defects that she experienced on discharge were minor visual disturbances and memory problems.