Manipulation Principles

During laparoscopic manipulation in children, the basic principles are the same as in adults with a few extra considerations. The operative area created by the pneumoperitoneum (or retroperitoneum) is smaller, often markedly so. This limits the movement potential,

It is helpful to take time at the beginning of a case to orient to the anatomy and the proximity of associated structures, all of which are much closer than in the adult.

particularly when handling sutures or retracting. This is not necessarily a direct problem, but requires a different pattern of movements than in adults. The amount of external movement needed to create a particular internal movement can be much less. The pneumoperitoneum is much more sensitive to loss of insufflating gas and small leaks during instrument changes, for example, can produce significant field of view losses. Increased gas flow can compensate for this but may produce excess pressures due to the lag time in pressure sensing. The best approach is to be aware of the problem and limit leakage.

The intraperitoneal space of the child looks different from that of the adult. In many ways it is much clearer to distinguish the anatomy, largely due to lack of fat. This may be disorienting to the experienced adult laparoscopist looking for different visual clues.

It is helpful to take time at the beginning of a case to orient to the anatomy and the proximity of associated structures, all of which are much closer than in the adult. Working in the small spaces of the child requires adjustments of movement and operative planning. While the anatomy may be more plainly visible, the proximity of structures demands a more meticulous and methodical pace to any procedure. Cautery injury is more readily possible and settings should be set lower for children. The amount of force needed to move tissues and organs is less and a degree of delicacy is called for.

The risk of cautery injury from direct contact is higher due to the small spaces, but also from the phenomenon of capacitive coupling (11-13). This is more likely in the smaller instruments due to increased current density at the level of the abdominal wall. There is also less abdominal wall tissue to diffuse the induced current. While this has not been a clinical problem with modern laparoscopic instruments and judicious use of cautery at relatively low power settings, all surgeons should be aware of its causes and potential.

Retroperitoneal access for renal surgery in the child increases the challenges of smaller spaces for surgical manipulation, even though it is considered advantageous over transperitoneal methods.

Tearing the peritoneum will allow insufflation, which reduces the working space in the retroperitoneum. Often this is only noted as a gradual dimin-ishment in the working space.

If the peritoneum is violated and insufflation limits the operative field, there are several options for correction. The peritoneal space may be vented using an angiocatheter placed near the lateral margin, the tear may be repaired directly and the peritoneal space evacuated, or a small tear may be opened widely to limit gas trapping in the peritoneum and permit a wider operative field.

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