PmWCaEATIalS is a relatively common condition. It has been estimated by Blumenthal and Probstein x that the incidence is about 1 in 600 admissions (0.16 per cent), based on the routine determination of serum amylase. The incidence of acute necrotizing pancreatitis in an autopsy series of 41,333 cases reported by MeWhorter = in 1952 was approximately 4 per thousand (0.4 per cent). The pancreas normally secretes a clear, colourless, and slightly mucoid fluid containing enzymes (trypsin, chymotrypsin, amylase, maltase, and lipase) which are concerned with digestion of protein, carbohydrates, and fat in the intestine. The action of these enzymes outside their normal environment accounts for the three major components of acute pancreatitis, namely (a) parenchymatous necrosis, (b) fat necrosis, and (c) haemorrhage. The pain of acute pancreatitis in its most severe form is excruciating and unrelenting. The patient writhes about in bed, shouting aloud in agony. Frequent doses of analgesics seem to alleviate the pain only very temporarily, and large doses are required. It is in this type of case that the use of some form of regional block would be most useful in controlling the extreme discomfort of the patient. Pain in the epigastrium, radiating through to the back, is the most prominent and distressing symptom of this condition, and the patient appears ashen grey in colour, breathing shallowly and rapidly and sweating profusely. In its most severe form, the shock may be so profound that death ensues rapidly. The pain is constant and is so relentless that the patient cannot rest. It thus leads to mental and physical exhaustion and contributes to the shock which is always present. NERVE SUPPLY OF THE PANCREAS The pancreas receives both sympathetic and parasympathetic nerves. The sympathetic nerves reach the pancreas through the greater and lesser splanchnic trunks arising from the fifth to tenth or eleventh thoracic sympathetic ganglia; the major nerve supply is through the greater splanchnic nerve. Parasympathetic fibres travel to the gland through the vagi and terminate in intrinsic pancreatic ganglia. These fibres are secretomotor. All the nerves to the pancreas, both afferent and efferent, pass through the coeliac plexus. Sympathetic preganglionic fibres reach the eoeliae or superior mesenteric ganglia, from which postganglionic fibres proceed along vessels to the pancreas (Fig. 1). Afferent pain fibres reach dorsal root ganglia from the pancreas by hitch-hiking along the sympathetic nerves

A series of 'light metal' MOFs containing SBUs based on Li + and Na + cations have been prepared using the silicon-centered linkers MexSi(p-C6H4CO2H)4-x (x = 2, 1, 0). The unipositive charge, small size, and oxophilic nature of the metal cations gives rise to some unusual and unique secondary building units (SBUs), including a 3D nodal structure built from sodium and oxygen ions when using the triacid linker (x = 1). The same linker with Li + cations generated a chiral, helical SBU, formed from achiral starting materials. 1D rod SBUs are observed for the diacid (x = 2) and tetra-acid (x = 0) linkers with both Li + and Na + cations, where the larger size of Na + compared to Li + leads to subtle differences in the constitution of the metal nodes.

From the departments of medicine, surgery, obstetrics and gynecology, and anesthesia,