Subfascial drainage for management of cerebrospinal fluid leakage after posterior spine surgery——A prospective study based on Poiseuille's law

摘要

Purpose:Up to date,some approaches retarding the flow of cerebrospinal fluid (CSF) could be regarded as direct applications of the fluid mechanics (Poiseuille's law).However,there is a lack of the research on the efficacy of subfascial drainage for management of CSF leak after spine surgery based on the law.This is a prospective and comparative study on subfascial drainage for CSF.Methods:Every four months in the three years from January 2010 to December 2012,the patients were enrolled respectively in Group A,Group B and Group C,in which,the drainage tube was discontinued within postoperative 3-4 days,5-6 days,7-10 days.Results and complications of postoperative CSF leak were investigated,and mean wound healing time (MWHT) of the three groups was compared.Results:A total of 108 cases (Group A/B/C:35/32/41) of CSF leak following posterior spine surgery were admitted to Tianjin Union Medicine Center,and 92 cases have been followed up for more than 1 year (follow-up rate of 85.2％).Preoperative demographics were similar among the 3 groups.In Group A,7 patients developed CSF leak through the wound (CSFLW),of which S cases had to undergo reoperation.One case in Group A was confirmed to have pseudomeningocele at the 1st month after surgery.The MWHT was (16.6 ± 3.6) days.In Group B,3 patients developed CSFLW and cured by reoperation,in which 1 case of superficial infection recovered well after reoperation.MWHT was (11.4 ± 2.2) days.In Group C,CSFLW was not found and MWHT was (10.1 ± 2.9) days.The differences of MWHT among Groups A,B and C were statistically significant.Conclusion:Postoperative subfascial drainage,which is used to decrease the subfascial space pressure (P2),would help wound healing.When it is placed for more than 7 days,the wound resistance (Rw)would be strong enough to withstand the subarachnoid pressure (P1).Meanwhile,the power transduction in a sequence of Rw ＞ P2＞P1 will indirectly retard CSF leak at the durotomy site and accordingly facilitate the healing of damaged spinal dura mater.