Thoracoabdominal aneurysmectomy: Operative steps for Crawford extent II repair

Cerebrospinal fluid production rate in various pathological conditions: a preliminary study

INTRODUCTION

The cerebrospinal fluid (CSF) production rate in humans is not clearly defined but is estimated to be 18-24 ml/h (Trevisi et al Croat Med J 55(4):377-387 (24); Casey and Vries Childs Nerv Syst 5(5):332-334 (8)). A frequent clinical observation is that patients often drain higher volumes of CSF than can be explained by the assumed 'normal' CSF production rate (PRcsf). In the National Hospital for Neurology and Neurosurgery PRcsf was recorded in a variety of common neurosurgical pathologies using LiquoGuard7, an automated peristaltic pump that accurately controls CSF drainage and maintains a pre-set CSF pressure.

METHODS

A prospective observational study was performed from September 2021 onwards, on all patients in the National Hospital for Neurology and Neurosurgery who required CSF drainage as part of their ongoing treatment. The external drain was connected to a LiquoGuard7 pump (Möller Medical GmbH, Fulda, Germany), and the internal software of LiquoGuard7 was used to measure PRcsf. Statistical analysis used SPSS (version 25.0, IBM) by paired t test, comparing measured rates to hypothetical 'normal' CSF production rates calculated and published by Ekstedt (16-34ml/h) (Ekstedt J Neurol Neurosurg Psychiatry 41(4):345-353 (14)), assuming a similar distribution.

RESULTS

PRcsf was calculated in 164 patients. Suspected normal pressure hydrocephalus (n=41): PRcsf of 79ml/h±20SD (p<0.0001). Post-surgical CSF leak (n=26): PRcsf of 90ml/h±20SD (p<0.0001). Subarachnoid haemorrhage (n=34): PRcsf of 143ml/h±9SD (p<0.0001). Intracerebral haemorrhage (n=22): PRcsf of 137ml/h±20SD (p<0.0001). Spinal lesions (n=7): PRcsf of 130ml/h±20SD (p<0.0032). Pituitary adenomas (n=10): PRcsf of 29 ml/h±9SD (p<0.049). Idiopathic intracranial hypertension (n=15): PRcsf of 86ml/h±10SD (p<0.0001). Decompensated long-standing overt ventriculomegaly (n=4): PRcsf of 65ml/h±10SD (p<0.0001). Cerebral infection (n=5): PRcsf of 90ml/h±20SD (p<0.0001).

CONCLUSION

Net CSF production rate may be higher than expected in many conditions, as measured with new device LiquoGuard7 through the study of net flow rate, which may have implications for clinical decisions on CSF diversion. The conventional understanding of CSF production and circulation does not explain the findings of this study. More extensive studies are needed to validate this technique.

Thoracoabdominal Aneurysm Repair During Early Stage of Pregnancy: Can and Should We Save the Baby?

Aortic dissection during pregnancy is a life-threatening condition for both mother and fetus. We present the case of a 34-year-old woman with a rapidly expanding abdominal aorta in the context of a chronic type B aortic dissection. A 4 to 6 weeks' viable pregnancy was incidentally diagnosed during the preoperative workup. She underwent urgent extent II thoracoabdominal aortic aneurysm repair with left-sided heart bypass. Postoperatively, vaginal ultrasound evaluation confirmed viability of the fetus, but the patient wished to terminate the pregnancy because of the possible unknown hypoxic effects on the fetus.

Distal Perfusion With Modified Centrifugal Pump Circuit in Thoracic and Thoracoabdominal Aortic Aneurysm Repair

OBJECTIVE

The left heart bypass is currently the most frequent adjunct to provide distal aortic perfusion during aortic clamping. However, closed-circuits cannot respond to sudden hemodynamic fluctuations during aortic clamping which may lead to complications. In this report, we aim to give the technical aspects of reservoir-added centrifugal pump circuit system, its implementation and the clinical outcomes.

METHODS

Between 2002 and 2020, the data of 35 patients underwent aortic aneurysm repair with the use of modified pump circuit were analyzed. The mean age was 53.4 years (range 24-73) and 91.4% of all was male. Preoperative demographics, intraoperative pump data and postoperative clinical outcomes were reported.

RESULTS

Thoracoabdominal incision was used in 22 patients (62.9%) and cerebrospinal fluid (CSF) drainage catheter was placed in 15 patients (42.9%). The left inferior pulmonary vein for outflow and the left femoral artery for inflow cannulation were used preferably. Median duration of pump support was 50 mins (13-121) in the cohort. The median transfusion of red packed cells was 2 units. Renal failure was observed in two patients and permanent paraplegia in one patient. Only one patient died in the elective group (1/34) and one patient in the emergent.

CONCLUSIONS

The reservoir-added centrifugal pump is an effective, practical, and flexible perfusion system which should be in the armamentarium of surgeons in order to solve difficult problems during open repair of descending and thoracoabdominal aortic aneurysms.