Pulmonary complications following endotracheal intubation for anesthesia in breech extraction.

A 28-year-old, healthy pregnant patient developed bilateral pneumothorax, subcutaneous emphysema, pneumomediastinum, pneumoretroperitoneum and pneumoperitoneum following endotracheal intubation and manual ventilation during general anesthesia for breech extraction. It is likely that positive-pressure ventilation was the cause for this very rare combination of complications. Early recognition and treatment may prevent such a catastrophe.

Preservation of myocardial contractility in hemorrhagic shock with methylprednisolone.

The left anterior descending or left circumflex coronary artery was cannulated selectively in 10 dogs. Methylprednisolone, 1 mg per kilogram of body weight, was injected into the artery and the cannula was withdrawn. The animals were then subjected to hemorrhagic shock for 90 minutes. Retransfusion to prestudy blood pressure was then accomplished. The electrocardiogram, arterial blood pressure, contractile force, and first derivative of contractile force were recorded continously both from the areas that were pretreated and those that were not, the controls. Contractile force in the control area was reduced to 32 +/- 3.2% of the preshock period after 90 minutes of shock, whereas in the pretreated area it was twice as high at the same time. Ten minutes after transfusion, the contractile force of the pretreated area exceeded the preshock level, whereas the recovery of contractile force in the control area reached only 70% of the preshock level. This study shows that intracoronary infusion of methylpredisolone can afford myocardial protection in hemorrhagic shock to a significant degree.

[Preliminary experience with laparoscopic repair of inguinal hernias].

During 1992-1996 we performed 163 laparoscopic hernia repairs in 100 men and 2 women. The mean age was 50.6; and in 61 the operation was bilateral, 66 were by transabdominal preperitoneal approach and 36 by total extra-peritoneal approach. There were only a few minor complications and total recurrence rate was only 4.3%, partly attributable to our learning curve. Laparoscopic inguinal herniorrhaphy reduces postoperative incisional and muscular pain and causes less disruption in the postoperative period than open repair. Return to normal activity and work is faster for laparoscopic than for open repair, but operating room costs are higher (time and equipment). However, economic advantages for the national economy should be considered.

[Video-assisted thoracoscopic surgery for diagnosis of pulmonary lesions].

23 patients (age 11-66 years) underwent video-assisted thoracoscopic biopsy for diffuse disease or peripheral nodular lesions of the lung. 12 had been previously treated for extrapulmonary malignancy and lung biopsy was done for suspicious metastases. In all cases except 1, lesions were identified and biopsied by thoracoscopy. The postoperative course was easier and shorter as compared to thoracotomy and the mean hospital stay was only 2.5 days. Thoracoscopic lung biopsy is a safe, effective and accurate diagnostic modality for diffuse lung disease and peripheral lesions. It is associated with minimal postoperative pain and discomfort, short hospital stay, early return to normal activity, and gives good cosmetic results.

[First experiences with retroperitoneoscopic lumbar sympathectomy].

We present our initial experience with retroperitoneoscopic lumbar sympathectomy in a series of 5 men aged 25-45 years. 3 suffered from ischemia of the lower limbs due to Buerger's disease, 1 had severe reflex sympathetic dystrophy and 1 had vasculitis with severe, non-healing lower leg ulcers. The right retroperitoneal space was developed with a dissecting balloon-trocar introduced via a small lateral muscle-splitting flank incision. 2 additional 5 mm trocars were used for instrumentation and clipping. L2-L3 or L3-L4 ganglia were resected; mean operating time was 120 minutes. Only oral analgesics were needed for postoperative pain control and oral food intake was resumed the following morning. The procedure was successful in all and was without complications. Mean hospital stay was 2 days. All patients reported significant relief of ischemia or dystrophic pain and/or improvement in trophic changes in the extremities. In the patient with leg ulcers, the largest was successfully covered with a skin graft. The retroperitoneoscopic approach to lumbar sympathectomy successfully combines the advantages of minimal invasive surgery and the reliability and effectiveness of well-established open sympathectomy.

[Laparoscopic colonic resection].

We present our initial experience with laparoscopic colonic resection in 15 patients: adenocarcinoma of the colon, 10 cases, giant villous adenoma (2), arteriovenous malformation (2), and a case of benign stricture. Mean operating time was 190 minutes and there were no intraoperative complications. The margins of resection and number of resected lymph nodes in patients with malignancy were comparable to those in the conventionally operated. Mean postoperative hospital stay was 6.1 days. During a maximum follow-up of 15 months there were no wound or trocar-site recurrences. We conclude that laparoscopic colonic resection is technically feasible and safe. However, its use for treating malignant diseases of the colon needs further study.

Visual failure and recovery after thrombosis of a giant carotid ophthalmic aneurysm following vascular bypass and carotid artery ligation.

Thrombosis via Hunterian ligation, with or without high-flow bypass, is the definitive treatment for unclippable giant aneurysms; however, secondary deterioration may occur. We present a 67-year-old woman with an unclippable giant (33mm) carotid ophthalmic aneurysm. High-flow external carotid artery to middle cerebral artery bypass and proximal cervical internal carotid artery Hunterian ligation achieved complete thrombosis. Subsequent expansion of the thrombosed aneurysm created mass effect with hydrocephalus, leading to marked cognitive and visual decline. Aneurysmal decompression led to improved vision and near-normal neurological function.

Amplified spontaneous emission in Cassegrainian amplifiers.

We consider all possible paths for amplified spontaneous emission (ASE) in multipass laser amplifiers using a Cassegrainian telescope geometry. In particular, we study ASE which is reflected back into the medium off the telescope mirrors themselves. These ASE components are unavoidable in this amplifier geometry. We show that there is a component of the ASE which makes approximately double the number of passes through the amplifier as the laser signal makes. We also show that these high order ASE components are also present in amplifiers which are almost Cassegrainian. They cannot be eliminated by changing the ratio of the scraper and hole radii or the separation of the mirrors. It is likely that these ASE components will be more significant in pulsed lasers than cw lasers.

Epidural capsaicin produces prolonged segmental analgesia in the rat.

The effect of epidural capsaicin injections on the thermal nociceptive threshold of unrestrained freely moving adult rats was examined. Capsaicin solution (1% 0.05 ml, 0.1 ml) was injected in a single dose or in two consecutive doses through an indwelling lumbar epidural catheter. Effects were compared with 1 ml 1% capsaicin injected intraperitoneally. Twelve rats served as sham-treated and vehicle controls. Nociceptive thermal stimuli were brief pulses of CO2 laser radiation directed at three body areas, hind limb, forelimb, and pinna. Capsaicin caused prolonged, segmental thermal analgesia. Maximal nociceptive threshold values in the hind limbs, attained within 24 h of epidural injection, were 2.5 (P less than or equal to 0.006) and 5.3 (P less than or equal to 0.0005) time control values for the 0.05-ml and 0.1-ml doses, respectively. Response thresholds in the forelimbs and pinna were unaffected. Two-stage epidural injection of capsaicin led to a roughly twofold elevation of threshold, as well as prolongation of the analgesia to about 14 days. Intraperitoneal injection of capsaicin resulted in elevation of nociceptive threshold which included all body areas tested. These results indicate that epidural application of capsaicin at the lumbar spinal level produced a profound and long-lasting segmental analgesia.

Postischemic intestinal motility in rat is inversely correlated to length of ischemia. An in vivo animal model.

An inverse correlation between postischemic gastrointestinal motility and the length of intestinal ischemia was found in an animal model. Intestinal ischemia was caused without concurrent laparotomy and for a predetermined time period (ischemia time) by pulling on an external nylon thread that was threaded through a double-lumen catheter. This catheter was passed into the abdominal cavity to encircle the superior mesenteric artery. Gastrointestinal motility was determined by the introduction of a color-marked meal into the animal's stomach and the measurement of the proportionate length of the small bowel filled with it (transit index). This simple and reliable animal model can also be used for the evaluation of techniques and pharmacological manipulations aimed at modulation of the effects of intestinal ischemia on intestinal motility and its consequences.

Epidural anesthesia accelerates the recovery of postischemic bowel motility in the rat.

BACKGROUND: Intestinal ischemia is associated with derangement of gastrointestinal motility. Uncontrolled clinical observations that bupivacaine injected into the epidural space causes faster recovery of bowel motility after various abdominal operations led us to assess the hypothesis that epidural anesthesia can hasten the recovery of gastrointestinal motility in the immediate postischemic period. METHODS: Gut motility studies were performed in rats in which epidural anesthesia and intestinal ischemia could be initiated without the need to provoke surgical trauma. Epidural lidocaine was compared to epidural saline in their effect on intestinal motility after a 30-min period of bowel ischemia. RESULTS: Total ischemia to the small bowel resulted in pronounced postischemic adynamic ileus as evidenced by only 0.7% of the total length of the small bowel filled with a marker meal at the end of the study period (transit index) compared with 84.4% in the control group. Lidocaine epidural anesthesia caused significantly more rapid resolution of the adynamic ileus (60.3% of the bowel filled with the marker meal vs. 30.9% in the controls in which saline was injected). CONCLUSIONS: Epidural lidocaine compared to epidural saline hastens the recovery of gastrointestinal motility in rats after a 30-min period of bowel ischemia. This effect may be elicited by attenuation of sympathetic efferent inhibitory pathways or by vasodilatation caused by the sympathetic block. These results suggest that lidocaine epidural block not only alleviates pain in situations of ischemic injury to the bowel but may also hasten the recovery from postischemic paralytic ileus.