الفهرس 
Pathophysiology of main respiratory diseasesOnly 14 pages are availabe for public view
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Abstract
Advantages of regional anesthesia are multiple. Patients have less emesis than after general anesthesia and experience less postoperative pain. The ability to be awake during surgery and be able to communicate with the surgeon can be perceived as an advantage by many patients and is a requirement for pain mapping in patients with nonspecific pain syndromes. Regional anesthesia is also cost effective and conducive to accelerating the discharge process in selected cases.
Occasionally patients having underlying respiratory diseases which may be obstructive or restrictive lung diseases require other types of surgery, but present significant challenges to the anesthetist because of impaired organ function.
Regional anesthesia may have much to offer such patients and we here report one who underwent successfully a laparoscopic surgeries under segmental subarachnoid (spinal) anesthesia performed at the low thoracic level
The first anxiety is that puncturing the dura mater in the thoracic region can lead to needle damage to the spinal cord, avoidance of this risk being the main reason why spinal anaesthesia is traditionally performed at the lumbar level.
This anxiety has been increased by a report that the accidental performance of spinal anaesthesia at a higher level than the intended one of L2–L3 can result in spinal cord damage.
However, consultation with radiological and neurological colleagues revealed that spinal puncture at the cervical and thoracic levels was regular practice for myelography when that investigation was used more widely.
Measuring the space between the dura mater and the mid to lower thoracic spinal cord on MRI scans showed that its width is actually greater than that of the epidural space at that level because the thoracic spinal cord lies anteriorly in the theca. Thus cautious use of intrathecal injection in the thoracic segments may be as much an option as epidural block for the experienced clinician.
The lumbar spinal cord is situated more dorsally and takes up more space because of the lumbar enlargement so that it is at greater risk of needle damage as shown by Reynolds’s reports of pain and paraesthesiae when needles were inserted at that level.
The second anxiety is that the extensive thoracic nerve block produced might result in ventilatory impairment. The main inspiratory muscle, the diaphragm, will be unaffected because it is innervated from the cervical level, and expiration is normally a passive phenomenon at rest.
However, forceful expiration and coughing will be affected because they are generated primarily by the muscles of the anterior abdominal wall which are innervated by the thoracic nerves.
The use of very low doses of local anaesthetic should minimize the degree of nerve block, and thus muscle weakness, but the technique could have disastrous effects in an individual patient with a pattern of obstructive airways disease dependent on active expiration to maintain lung ventilation.
The pressure of the pneumoperitoneum also needs to be controlled carefully during surgery to ensure adequate diaphragmatic excursion. Clearly, patients receiving this technique must be assessed very carefully and managed by anesthetists with considerable experience of regional anesthesia.
It may be argued that this particular patient could have been managed using other anesthetic techniques, particularly general anesthesia with artificial ventilation, but this ignores the refusal of two separate groups of experienced clinicians to use that, or any other, anesthetic approach.
A number of other regional techniques (catheter spinal, thoracic epidural, paravertebral or infiltration with coeliac plexus block) were also possible.
However, a combined spinal/epidural was chosen because of personal familiarity with a highly reliable technique which can provide profound block (so minimizing the need for sedation) for surgery and good quality analgesia thereafter without the need for large doses of any drug.
There is never a ‘right’ way to anaesthetize such a patient, but what is described here is an option to expand the boundaries of regional anesthesia by performing spinal anesthesia in a new way which may be to the advantage of certain patients.