title: Intracranial pressure and haemodynamic changes during the tunnelling phase of ventriculoperitoneal shunt insertion.
abstract: OBJECTIVE
  The tunnelling phase of ventriculoperitoneal shunt insertion is the most painful part but patients are often given inadequate opioid analgesic for fear of post operative delayed recovery and/or respiratory depression. This may result in an increase in intracranial pressure.
  
  
  METHODS
  Twenty adults scheduled to undergo ventriculoperitoneal shunt insertion were administered standard anaesthesia. Monitoring included heart rate, electrocardiogram, end-tidal carbon dioxide, invasive blood pressure, and oxygen saturation. Intracranial pressure was monitored by placing the ventricular end of shunt catheter in the dilated lateral ventricle. Five minutes before tunnelling, fentanyl 1 microg kg(-1) was administered. Mean arterial pressure, heart rate and intracranial pressure were recorded during tunnelling and subsequently at 1-min interval for 5 min. Data were analysed using t-test and repeated measured test.
  
  
  RESULTS
  Tunnelling caused significant increase in mean arterial pressure (from 81.4 +/- 11.0 to 110.9 +/- 15.3 mmHg, P < 0.05), intracranial pressure (from 21.4 +/- 8.1 to 29.2 +/- 12.5 mmHg, P < 0.05) and heart rate (from 74.4 +/- 13.8 to 94.1 +/- 17.8 beats min(-1), P < 0.05). Whereas, the increase in haemodynamic parameters persisted for 3 min post-tunnelling, elevated intracranial pressure lasted for 2 min.
  
  
  CONCLUSIONS
  Tunnelling significantly increases intracranial pressure and blood pressure despite prior fentanyl administration. This may be deleterious in the presence of intracranial pathology.
authors.affiliation: All India Institute of Medical Sciences, Department of Neuroanaesthesiology, New Delhi, India.
authors.forename: H
authors.initials: H
authors.lastname: Prabhakar
authors.forename: G P
authors.initials: GP
authors.lastname: Rath
authors.forename: P K
authors.initials: PK
authors.lastname: Bithal
authors.forename: R S
authors.initials: RS
authors.lastname: Chouhan
mesh_terms: D000293:Adolescent; D000328:Adult; D000768:Anesthesia, General; D001794:Blood Pressure; D002560:Cerebrovascular Circulation; D005260:Female; D006339:Heart Rate; D006439:Hemodynamics; D006801:Humans; D007427:Intracranial Pressure; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D017287:Ventriculoperitoneal Shunt