Experimental renal preservation by normothermic resuscitation perfusion with autologous blood.

BACKGROUND: Normothermic perfusion (NP) has the potential to improve metabolic support and maintain the viability of ischaemically damaged organs. This study investigated the effects of NP compared with current methods of organ preservation in a model of controlled non-heart-beating donor (NHBD) kidneys. METHODS: Porcine kidneys (n = 6 in each group) were subjected to 10 min warm ischaemia and then preserved as follows: 2 h cold storage (CS) in ice (CS2 group), 18 h CS (CS18 group), 18 h cold machine perfusion (CP group) or 16 h CS + 2 h NP (NP group). Renal haemodynamics and function were measured during 3 h reperfusion with autologous blood using an isolated organ perfusion system. RESULTS: Increasing CS from 2 to 18 h reduced renal blood flow (mean(s.d.) area under the curve (AUC) 444(57) versus 325(70) ml per 100 g; P = 0.004), but this was restored by NP (563(119) ml per 100 g; P = 0.035 versus CS18). Renal function was also better in CS2, CP and NP groups than in the CS18 group (mean(s.d.) serum creatinine fall 92(6), 79(9) and 64(17) versus 44(13) per cent respectively; P = 0.001). The AUC for serum creatinine was significantly lower with CS for 2 h than for 18 h (mean(s.d.) 1102(2600) versus 2156(401) micromol/l.h; P = 0.001), although values in CP and NP groups were not significantly different from those in the CS2 group (1354(300) and 1756(280) micromol/l.h respectively). Two hours of NP increased the adenosine 3'-triphosphate : adenosine 3'-diphosphate ratio to a significantly higher level than the preperfusion values in all other groups (P = 0.046). CONCLUSION: NP with oxygenated blood was able to restore depleted ATP levels and reverse some of the deleterious effects of CS.

Pre-incision infiltration of local anesthetic reduces postoperative pain with no effects on bruising and wound cosmesis after thyroid surgery.

Optimizing postoperative pain control is an important aspect in perioperative patient care. The aim of this study was to investigate the efficacy of preincision local anesthetic infiltration in postoperative pain management for thyroid surgery and its relationship to bruising and wound cosmesis. In a randomized single-blinded study, 39 consecutive patients listed for thyroid surgery were assigned into two groups. Group I (n = 19) received subcuticular preincision infiltration with 10 ml of bupivacaine (0.5%) and Group II (n = 20) received no infiltration. Postoperatively, the pain experienced was evaluated by two methods: verbal response scores and linear analogue scores (0-100 mm) at different time intervals following surgery. Bruising and cosmetic effects resulting from surgery were assessed using a linear analogue score at discharge. The two groups were well matched for confounding variables. Pain scores were significantly different at 6 hours post operatively (p = 0.0341) with mean scores Group I = 33 and Group II = 50, but this difference disappeared at 24 hours. No patients (0%) received IV morphine in Group I compared to 5 patients (25%) in Group II. There was no significant difference in the mean bruising scores (p = 0.8864) and mean cosmetic scores (p = 0.3339) at discharge. Preincision infiltration with bupivacaine provides easy and better analgesic control postoperatively in patients following thyroid surgery with no effects on bruising or wound cosmesis.

Effect of nifedipine on renal transplant rejection.

The effect of early nifedipine therapy on acute renal allograft rejection was studied in 170 adult cadaveric transplant recipients. Acute rejection occurring in the first 3 months after transplantation was diagnosed by Tru-cut biopsy and the severity of each rejection episode assessed histologically. The incidence of acute rejection was significantly lower in patients treated with nifedipine (29 of 80; 36 per cent) than in controls (52 of 90; 58 per cent) (P < 0.01) and there was a higher proportion of histologically mild rejection episodes in the former group (P < 0.01). Multivariate analysis confirmed that nifedipine exerted a significant independent effect on the incidence of early acute rejection. Other factors identified in the multivariate model as influencing rejection were human leucocyte antigen (HLA) matching at the DR locus, blood level of cyclosporin during the first week, HLA matching at the B locus, donor age and donor sex. The 1-year graft survival rate was 88.6 per cent in patients given nifedipine and 63.8 per cent in controls (P < 0.02). These data suggest that nifedipine therapy has a useful role in human renal transplantation.

Factors influencing the healing of distal amputations performed for lower limb ischaemia.

A total of 235 toes were amputated during 125 operations on 100 consecutive patients with lower limb ischaemia. The overall amputation wound healing rate for the series was 58.4 per cent and limb salvage was achieved in 66 patients. Toe amputation was performed under local anaesthesia in 57 cases and 32 (56 per cent) of these healed primarily, not significantly different from the healing rate of 41 (60 per cent) of 68 under general anaesthesia. Reconstructive arterial surgery was performed in conjunction with toe amputation in 39 patients; the healing rate with reconstruction was 32 (82 per cent) of 39, significantly better than the 41 (48 per cent) of 86 patients not undergoing bypass surgery (P less than 0.001). There was no difference in healing rates when comparing diabetic and non-diabetic patients. Multiple regression analysis demonstrated that reconstructive arterial surgery was the only factor which had an independent and significant influence on toe amputation healing. The use of local anaesthesia for distal amputation has no deleterious effects on wound healing.

Inhibition of experimental colorectal carcinogenesis by dietary N-6 polyunsaturated fats.

The influence of dietary fats on azoxymethane-induced colorectal carcinogenesis and erythrocyte, adipose, colon mucosa and tumour tissue fatty acids was investigated in 228 Wistar rats. The two main diets compared were beef suet rich in saturated fatty acids and corn oil rich in a linoleic acid, an N-6 polyunsaturated fatty acid. The animals were placed in one of four dietary groups: A = 5% saturated fat, B = 20% saturated fat, C = 5% N-6 fat and D = 20% N-6 fat. There was no difference in the number of adenomas between any of the dietary groups. The mean (+/- SEM) carcinoma yield per rat was A = 0.93 +/- 0.28, B = 1.93 +/- 0.50, C = 0.70 +/- 0.07, D = 0.13 +/- 0.04; the tumour yields in rats fed the saturated fat diets were significantly different from each other and from those fed the N-6 fat diets. The fatty acid profiles in all tissues were dependent upon the type and level of dietary fat and the tissue type. Arachidonate was higher in tumours compared to normal mucosa. Significant correlations were found between adipose linoleate (reflecting dietary intake) and tumour oleate and tumour arachidonate but not with the colorectal mucosa of control animals. This is the first in vivo study to show reduced colorectal carcinogenesis by N-6 polyunsaturated fatty acids.

Intraoperative air testing of colorectal anastomoses: a prospective, randomized trial.

A total of 145 consecutive patients receiving a colorectal anastomosis were randomized to 'test' or 'no test' once the anastomosis had been completed. Anastomotic testing was performed with the pelvis filled with saline and the rectum distended by sigmoidoscopic insufflation of air. Any leaks demonstrated were oversewn. A water-soluble contrast enema was performed on the tenth postoperative day. Seventy-four patients were randomized to 'test' and 71 to 'no test' but one patient was withdrawn from each group leaving a total of 143 for analysis. The two groups were well matched for age, sex, diagnosis and operative details. Eighteen (25 per cent) air leaks were detected and repaired in the 'test' group. After operation there were three (4 per cent) clinical leaks in the 'test' group and ten (14 per cent) in the 'no test' group (Fisher's exact test, P = 0.043). There were eight (11 per cent) radiological leaks in the 'test' group and 20 (29 per cent) in the 'no test' group (P = 0.006). Intraoperative air testing and repair of colorectal anastomoses significantly reduces the risk of postoperative clinical and radiological leaks.