Gas embolization of the liver in a rat model of rapid decompression

Occurrence of liver gas embolism after rapid decompression was assessed in 31 female rats that were decompressed in 12 min after 42 min of compression at 7 ATA (protocol A). Sixteen rats died after decompression (group I). Of the surviving rats, seven were killed at 3 h (group II), and eight at 24 h (group III). In group I, bubbles were visible in the right heart, aortic arch, liver, and mesenteric veins and on the intestinal surface. Histology showed perilobular microcavities in sinusoids, interstitial spaces, and hepatocytes. In group II, liver gas was visible in two rats. Perilobular vacuolization and significant plasma aminotransferase increase were present. In group III, liver edema was evident at gross examination in all cases. Histology showed perilobular cell swelling, vacuolization, or hydropic degeneration. Compared with basal, enzymatic markers of liver damage increased significantly. An additional 14 rats were decompressed twice (protocol B). Overall mortality was 93%. In addition to diffuse hydropic degeneration, centrilobular necrosis was frequently observed after the second decompression. Additionally, 10 rats were exposed to three decompression sessions (protocol C) with doubled decompression time. Their mortality rate decreased to 20%, but enzymatic markers still increased in surviving rats compared with predecompression, and perilobular cell swelling and vacuolization were present in five rats. Study challenges were 1) liver is not part of the pathophysiology of decompression in the existing paradigm, and 2) although significant cellular necrosis was observed in few animals, zonal or diffuse hepatocellular damage associated with liver dysfunction was frequently demonstrated. Liver participation in human decompression sickness should be looked for and clinically evaluated

High-Volume Transanal Surgery with CPH34 HV for the Treatment of III-IV Degree Haemorrhoids: Final Short-Term Results of an Italian Multicenter Clinical Study

The clinical chart of 621 patients with III-IV haemorrhoids undergoing Stapled Hemorrhoidopexy (SH) with CPH34 HV in 2012-2014 was consecutively reviewed to assess its safety and efficacy after at least 12 months of follow-up. Mean volume of prolapsectomy was significantly higher (13.0 mL; SD, 1.4) in larger prolapse (9.3 mL; SD, 1.2) (p < 0.001). Residual or recurrent haemorrhoids occurred in 11 of 621 patients (1.8%) and in 12 of 581 patients (1.9%), respectively. Relapse was correlated with higher preoperative Constipation Scoring System (CSS) (p = 0.000), Pescatori's degree (p = 0.000), Goligher's grade (p = 0.003), prolapse exceeding half of the length of the Circular Anal Dilator (CAD) (p = 0.000), and higher volume of prolapsectomy (p = 0.000). At regression analysis, only the preoperative CSS, Pescatori's degree, Goligher's grade, and volume of resection were significantly predictive of relapse. A high level of satisfaction (VAS = 8.6; SD, 1.0) coupled with a reduction of 12-month CSS (Δ preoperative CSS/12 mo CSS = 3.4, SD, 2.0; p < 0.001) was observed. The wider prolapsectomy achievable with CPH34 HV determined an overall 3.7% relapse rate in patients with high prevalence of large internal rectal prolapse, coupled with high satisfaction index, significant reduction of CSS, and very low complication rates

Gas embolization of the liver in a rat model of rapid decompression.

Occurrence of liver gas embolism after rapid decompression was assessed in 31 female rats that were decompressed in 12 min after 42 min of compression at 7 ATA (protocol A). Sixteen rats died after decompression (group I). Of the surviving rats, seven were killed at 3 h (group II), and eight at 24 h (group III). In group I, bubbles were visible in the right heart, aortic arch, liver, and mesenteric veins and on the intestinal surface. Histology showed perilobular microcavities in sinusoids, interstitial spaces, and hepatocytes. In group II, liver gas was visible in two rats. Perilobular vacuolization and significant plasma aminotransferase increase were present. In group III, liver edema was evident at gross examination in all cases. Histology showed perilobular cell swelling, vacuolization, or hydropic degeneration. Compared with basal, enzymatic markers of liver damage increased significantly. An additional 14 rats were decompressed twice (protocol B). Overall mortality was 93%. In addition to diffuse hydropic degeneration, centrilobular necrosis was frequently observed after the second decompression. Additionally, 10 rats were exposed to three decompression sessions (protocol C) with doubled decompression time. Their mortality rate decreased to 20%, but enzymatic markers still increased in surviving rats compared with predecompression, and perilobular cell swelling and vacuolization were present in five rats. Study challenges were 1) liver is not part of the pathophysiology of decompression in the existing paradigm, and 2) although significant cellular necrosis was observed in few animals, zonal or diffuse hepatocellular damage associated with liver dysfunction was frequently demonstrated. Liver participation in human decompression sickness should be looked for and clinically evaluated

POST-DIVE ULTRASOUND DETECTION OF GAS IN THE LIVER OF RATS AND SCUBA DIVERS

In a previous study we obtained histologic documentation of liver gas embolism in the rat model of rapid decompression. Aim of the study was to assess in the same model occurrence and time course of liver embolism using 2D ultrasound imaging, and to explore by this means putative liver gas embolism in recreational scuba divers. Following 42 min compression at 7 ATA breathing air and 12 min decompression, 8 surviving female rats were anesthetized and the liver imaged by ultrasound at 20 min intervals up to 120 min. A significant enhancement of echo signal was recorded from 60 to 120 min as compared to earlier post-decompression times. Enzymatic markers of liver damage (AST, ALT, GGT) increased significantly at 24 h upon decompression. Twelve healthy experienced divers were studied basally and at 15-min intervals up to 60 min following a 30-min scuba dive at 30 msw depth. At 30 min upon surfacing echo images showed significant signal enhancement that progressed and plateaued at 45 and 60 min. Total bilirubin at 24 h increased significantly (p = 0.02) with respect to basal values although within the reference range. In conclusion, 2D ultrasound liver imaging allowed detection of gas embolism in the rat and defined the time course of gas accumulation. Its application to scuba divers revealed liver gas accumulation in all subjects in absence of clear-cut evidence of liver damage or of any symptom. The clinical significance of our findings remains to be investigated

Residual Prolapse in Patients with III-IV Degree Haemorrhoids Undergoing Stapled Haemorrhoidopexy with CPH34 HV. Results of an Italian Multicentric Clinical Study

Patientswith haemorrhoids and large internal rectal prolapse are at high risk of relapse after stapled haemorrhoidopexy (SH) due to the limited prolapse resection achievable with currently available staplers. Stapled transanal rectal resection (STARR) was tested to overcome such technological limitations, although it requires a double rectal resection. A novel stapler device, CPH34 HV, with a high volume stapler casing, was tested in a multicenter clinical study in order to assess its safety and efficacy in this clinical setting. Patients and Methods. The clinical chart of 430 patients (209 males and 221 females; mean age of 51 years; SD, 13.4 years) with third- to fourth-degree haemorrhoids undergoing SH in 2012-2013 was consecutively reviewed. Patients with symptoms of obstructed defecation syndrome (ODS), second-degree rectocele (2–4 cm), and a Wexner’s constipation score over 15 were excluded. Follow-up was scheduled at six and 12 months after the operation. Results. Three hundred forty-one patients (79.3%) had an internal rectal prolapse exceeding more than half of CAD. One technical failure of the device was reported (0.2%) without any untoward effect as for the operation; 1.3 stitch/patient (SD, 1.7) was required to achieve complete haemostasis of the suture line. The mean in-hospital stay was 1.6 days (SD, 1; range, 1–4). The mean volume of the doughnuts was significantly higher (13.8 mL; SD, 1.5) in patients with a large rectal prolapse than with smaller one (8.9 mL; SD, 0.7) (-value < 0.05). Residual and recurrent haemorrhoids occurred in eight out of 430 patients (1.8%) and in five out of 254 patients (1.9%), respectively, withmost of them having originally a large rectal prolapse. A high index of patient satisfaction (visual analogue scale = 8.9; SD, 0.9) coupled with a persistent reduction of constipation scores (CSS = 5.0, SD, 2.2) was observed. Conclusions.The wider prolapse resection well correlated with a clear-cut reduction of haemorrhoidal relapse, a high index of patient satisfaction, and clinically-relevant reduction of constipations scores coupled with satisfactory haemostatic properties of CPH34 HV