Italy was hit by a fresh public health scare on Monday following the death of several patients in a southern hospital who were given laughing gas instead of oxygen.
Two patients died last week at the hospital in Castellaneta near Taranto in the region of Puglia after being fed nitrous oxide, the common anaesthetic gas also known as laughing gas.
Prosecutors suspect the same blunder could be behind another six deaths on the hospital's new coronary intensive care ward since it opened on April 20.
Autopsies are being performed on the two most recent deceased patients, 73-year-old Cosima Ancona, who died last Friday and 82-year-old Pasquale Mazzone, who died two days earlier.
Mazzone's death failed to arouse suspicion because of his general poor health, doctors said. The previous deceased patients were also elderly and frail, they said.
But Ancona unexpectedly died before doctors' eyes during a minor operation for heart arrhythmia when her face mask sent fatal doses of nitrous oxide into her lungs instead of oxygen.
Investigators have ordered the bodies of the six other patients who died on the ward to be exhumed for autopsies.
Police on Monday raided the offices of Ossitalia, a Puglia company specialising in the installment of medical gas equipment which fitted the pipes connecting the hospital ward to external gas tanks.
Police swooped on the headquarters of Ossitalia in Bitonto near Bari seizing documents linked to the Castellaneta hospital contract and the installed gas system.
The health ministry also ordered inspections in some 70 other hospitals where gas equipment has been installed by Ossitalia.
Ossitalia chairman and founder Domenico Matera is already under investigation on possible manslaughter charges in connection with the death of another patient at a Tuscan clinic with Ossitalia equipment.
The 73-year-old patient died at Siena's Le Scotte clinic on February 27 after a gas tube mix-up.
Puglia prosecutors are considering placing Matera, 55, under investigation for multiple manslaughter.
The leading investigator, Taranto chief prosecutor Aldo Petrucci, said the Castellaneta hospital deaths appeared to be the result of a "macroscopic error" in the way the hospital gas system was installed.
But Matera's lawyers stressed that the system was finished and successfully tested in March 2005, when the hospital opened after 20 years of stop-start construction.
Ossitalia's lawyers said other firms had been involved with the gas system between 2005 and April 2007 when the coronary ward was opened.
"There's a two-year hole here and what needs to be verified is what happened to the gas equipment during that time," the lawyers said.
Health officials in the northern city of Udine and in the northwest region of Liguria said they were checking gas systems installed by Ossitalia in local hospitals and that so far, no problems had emerged.
Health Minister Livia Turco described the Puglia deaths as an "appalling tragedy", saying that "whoever made a mistake here will pay dearly".
STRING OF ERRORS BRING HEALTH SERVICE UNDER SCRUTINY.
The case dealt a fresh blow to public confidence in Italy's health service, which has been beset by a string of errors and apparently avoidable deaths over the past year.
In February, three patients at a Tuscan hospital were given transplants using organs from an HIV-positive donor.
The blunder was attributed to a senior laboratory worker who mistakenly put HIV negative on a form, clearing organs from the infected female donor for transplantation.
In another headline case in January, a 16-year-old girl from Vibo Valentia in Calabria entered a fatal coma when a power cut occurred in the hospital where she was being operated on for appendicitis.
Every year, between 4,500-7,000 patients die in Italy because of infections contracted while in hospital.
Hospital infections are considered a factor in another 21,000 patient deaths while up to 700,000 patients contract non-fatal infections.
Reports of poor hygiene and low safety standards sparked a nationwide inspection of public hospitals two months ago.
Less than half were given a clean bill of health, with 36.4% reported for breaching administrative norms, 17.4% for breaching building norms and 7.5% for breaching hygiene and cleanliness norms.
Southern regions were found to be the worst, with hospitals in Sicily, Calabria, Lazio around Rome and Campania around Naples proving the dirtiest.
